Shotcut tutorial · companion page
A door swings open onto a waterfall; a pillar wipes one scene away and brings in another. Both are the same idea — a hole in the top layer. When the footage is already green screened that hole costs one filter. When it is not, it costs 62 frames cut out by hand in Photoshop. This page covers both routes, with every setting read off the screen.
Reading in another language? Use the translate picker in the header, or your browser’s own translate command — the Shotcut and Photoshop tool, filter and control names are marked so they stay in English and still match what is on your screen.
Both transitions in this tutorial are the same mechanism. Two video tracks, the incoming scene underneath, the outgoing scene on top, and a moving hole in the top one. Everything else is about how that hole gets made.
The bottom track is whatever should appear. It is never filtered and never cut. If nothing shows through, the problem is always on the track above it, not this one.
The top track is the scene being wiped away. Wherever it is transparent, the track below shows through. That transparency is the entire effect — there is no transition preset involved anywhere.
If the footage already ships with a flat green area where the hole belongs, Chroma Key: Simple turns that colour transparent and you are done. Search for a pre-keyed version of what you need before doing anything else.
If it does not, every single frame has to be exported as a transparent PNG, cut out in a photo editor, saved, and reassembled. Thirty-four frames for the door, twenty-eight for the wipe. Ben spent thirty minutes on the door alone.
One thing worth saying plainly, because the filter names suggest otherwise: no Mask: From File, Mask: Simple Shape or Mask: Apply filter is used anywhere in this tutorial. On Shotcut 21.02.27 the only filter applied is Chroma Key: Simple. In the hard route the mask is not a filter at all — it is the alpha channel inside the PNG files.
[ the last tutorial that I showed you took me 30 minutes just to cut out that small sliver from the door, so save yourself the trouble if you can ]
Ben Espanto · 21:26
The video carries five chapters of its own, and the last of them stops at 20:06 with thirteen minutes still to run. The rest were derived by reading the frames; every derived card says so in its caption, and every timestamp was checked against the frame it points at. Click any screencap or timestamp to play that section from its exact second, right here in the card.
“In this tutorial, I’ll be showing you how to do two transitions. The door open mask transition and the mask wipe transition using the same technique.”
No interface on screen yet — this is the finished door-open effect playing as the cold open. A white door swings inward and, instead of a hallway, a waterfall scene is behind it. The video’s own chapter list calls this stretch Start; the whole of it is the pitch for both effects.
“This tutorial is going to be done on Shotcut version 21.02.27.”
Derived — this card is not one of the video’s own chapters; the chapter list has nothing between 0:00 and 1:10. Help → About Shotcut is open on screen and reads Shotcut version 21.02.27, Copyright © 2011-2021 Meltytech, LLC, licensed GNU General Public License v3.0. Menu paths and filter names moved after this build, so check yours against the table below.
“Hopefully, you’re able to find and download an already existing green screened version of an animation of a door being opened. Believe me, there are already tons online to save yourself the work.”
A stock green screen clip, which is what this whole route depends on. Chroma keying replaces one flat colour with transparency, so the animation has to ship with that colour already painted into the area you want to see through. Here the inside of the doorway is solid green before Shotcut ever opens it.
“And to get started, we’re going to need to create two tracks. So let’s start out with the waterfalls and I’m going to put that on the bottom track.”
Derived — this card is not one of the video’s own chapters; the chapter runs 1:10–5:00 as one block, and the track setup is a separate step inside it. The playlist holds waterfalls.mp4 at 00:00:36:08 and Stairs - 65860.mp4 at 00:00:10:00. On the timeline V1 carries the reveal (waterfalls.mp4) and V2 carries the door. Stacking order is the whole trick: whatever is on top gets holes punched in it.
“And for this one, we’re going to choose chroma key simple. And all of a sudden it’s transparent.”
Derived — this card is not one of the video’s own chapters; split out of the same 1:10–5:00 chapter. Select the top clip, open Filters, press + and pick Chroma Key: Simple. The panel shows Key color already on green and Distance at its default 28.8 % — neither value is changed anywhere in the video. If the key colour is wrong, the eyedropper beside the swatch samples it off the preview.
“Other video editors like Adobe Premiere and DaVinci Resolve have the ability to create complex mask shapes and selections using a pen tool or a Bezier curve within the software itself. Unfortunately, Shotcut at this current version of this video does not.”
The green overlay here is an illustration of the kind of freehand path selection Shotcut 21.02.27 has no tool for. It can make simple shapes — a rectangle, an ellipse — and compound shapes built from two of those, but it cannot trace an arbitrary outline. That single limitation is why the rest of the tutorial leaves the editor and goes to a photo editor that can save transparent PNG files.
“So this is the file that we have here. And as you can see, there’s an interior. But what we want to do is, when this door opens, we want it to open into this waterfall scene, just like that other one.”
Same two-track shape as the easy route, different source. V2 holds door-open-no-green01.mp4 — a real doorway with a real interior behind it, no green anywhere — and V1 holds waterfalls.mp4. Nothing shows through yet, because there is nothing for a key to remove.
“And so first what we need to do in this door open video is isolate all the frames that I’m going to need to modify. And so I’m going to cut it there using the little split tool or S right there.”
Derived — this card is not one of the video’s own chapters; the chapter How to Extract Frames from a Video runs 6:20–20:06, nearly fourteen minutes, so it is split here into real steps. Park the playhead at the moment the door is wide open and fills the frame, then press S (or the split button on the timeline toolbar) to cut there. In this clip the door is already ajar at frame one, so there is no second cut at the head — the whole leading segment is what gets exported.
“So while the clip that you want to extract is selected, all you have to do is copy it by clicking control C so that you can copy into the clipboard. And once you have it on the clipboard, you can click this source tab here.”
Derived — this card is not one of the video’s own chapters; same long chapter. With the segment selected press Ctrl+C, then click the Source tab under the player (it sits next to Project). The player now holds only that clipboard segment, with its own in and out points. This is the step the whole export depends on, and it is also the one that is easy to skip.
“And of course, we’re going to need to choose PNG because this needs to be a transparent file. And PNG is one of the only few that can actually do transparent images.”
Derived — this card is not one of the video’s own chapters; same long chapter. Open Export, scroll the preset tree to the bottom to the stills group and choose PNG — its siblings BMP, DPX, JPEG, PPM, TGA and TIFF are visible in the same group, and only PNG and TGA carry an alpha channel. Then press Advanced and change From from Timeline to Source. The frame here shows it already switched; two frames earlier it still read Timeline. Get this wrong and you export the entire timeline instead of your selection.
“Thankfully, there’s only 34 frames in this entire thing.”
Derived — this card is not one of the video’s own chapters; same long chapter. The export is named door open and the job runs in the Jobs panel. Windows Explorer then shows door-open-00001 through door-open-00034 — five-digit numbering, PNG File type — in the same folder as the sources. That count is the honest cost of this technique: thirty-four separate images, each of which has to be cut by hand.
“So now I need to open Photoshop. And then I’m going to need to go into that folder and drag every single one of these photo files into it, the 34 images.”
Derived — this card is not one of the video’s own chapters; same long chapter, and the point where the tutorial changes application. Drag the whole selection of PNG files onto Photoshop and each one opens as its own document tab. The status bar reads Doc: 5.93M/5.93M and the tab title reads RGB/8, which is exactly a 1920 × 1080 eight-bit frame — the canvas already matches the project, so nothing needs resizing.
“So this is the first frame of that video. And so all I need to do is go into the selection tool and I’m going to choose the polygon lasso tool. I’m going to create a selection here.”
Derived — this card is not one of the video’s own chapters; same long chapter. Double-click the locked Background layer first so it becomes Layer 0 — a background layer cannot hold transparency, and skipping this is the most common way this step fails. Then trace the doorway gap with the Polygonal Lasso Tool (options bar: Feather 0 px, Anti-alias ticked) and press Delete. The checkerboard on the right of the frame is the result. Polarity: what you delete is what the layer underneath will show through. Delete the wrong side and the effect inverts.
“So if this were the top layer and I add another layer underneath it… I’m just going to fill it with the color. Let’s say this red color. Edit fill. You’re going to see that it is transparent.”
Derived — this card is not one of the video’s own chapters; same long chapter. A checkerboard is hard to read against dark footage, so add a new layer, drag it below Layer 0, and Edit → Fill it with a loud red. The layers panel shows Layer 0 over Layer 1, Normal, Opacity 100%, Fill 100%. Any white fringe still showing against the red is a bit of the selection you missed — cut it now, then throw the red layer away before saving.
“Oops missed that part there. I’m going to come back there later and fix that. So let’s zoom in a little bit so I can fix.”
Derived — this card is not one of the video’s own chapters; same long chapter. The second image gets the same treatment, plus a zoomed-in cleanup of a white sliver the rough selection left behind. After that the video fast-forwards through the remaining images rather than showing all thirty-four. Saving is a plain Ctrl+S straight back over the same .png — no Save As, no flatten, no dialog, which is what keeps the alpha channel intact.
“And so all I need to do is go into open file. Find the first image which was door open 00001.”
Derived — this card is not one of the video’s own chapters; same long chapter. Open File and pick door-open-00001.png — the first of the series, not any other. The player shows a single still, which looks like nothing has worked. It has; the next step is what turns it back into a clip.
“And so with this image selected we then go to properties and all we have to do is click image sequence. And then all of a sudden you can see here it combined all those PNG images back into a video.”
Derived — this card is not one of the video’s own chapters; same long chapter, and the single most useful thing in this tutorial. Tick Image sequence in Properties and Shotcut reads every numbered file in the series as one clip. The panel then reads Resolution 1920x1080, Duration 00:00:01:10, Pixel aspect ratio 1 : 1 and Repeat 1 frames per picture. At 23.976024 fps that duration is thirty-four frames — exactly the count that went out.
“And what I’m going to do is I’m going to remove that area that we extracted from earlier. And I’m going to replace it with this new video with the cutouts that we just created.”
Derived — this card is not one of the video’s own chapters; same long chapter. Delete the original segment from V2 and drag the image-sequence clip into the gap it leaves. The timeline now reads door-open-00001.png on V2 over waterfalls.mp4 on V1, and the waterfall shows through the doorway. The white edges Ben points out are the price of a rough lasso, not a fault in the method.
“Here. Let’s render this. Let’s call this door open final. Four seconds pretty good.”
Derived — this card is not one of the video’s own chapters; the last piece of the How to Extract Frames from a Video chapter, which ends at 20:06. The save dialog opens on the previous name door-open-demo2 with Save as type on mp4 (*.mp4); it is renamed to door open final. The render takes about four seconds.
“One important component of the wiper object is that it has to span from the top of the screen all the way to the bottom. You don’t want any gaps because it will not look good when you do the wipe.”
Same technique, different job. Instead of a door revealing a scene, an object crossing the foreground — here one of the pillars in this hall — wipes one scene away and brings in another. The rule is absolute: the wiper has to touch the top and the bottom of the frame throughout, because any gap lets the outgoing scene leak through mid-wipe. The chapter list ends at this entry even though the video runs another thirteen minutes, so everything below is derived.
“So the bottom track is going to be the one that is going to be revealed… and if you don’t know how to create a new track just go to just right click the track, track operations and then add video track or control I.”
Derived — this card is not one of the video’s own chapters; the chapter list stops at 20:06; the rest is read off the frames. Right-click the track head, Track Operations → Add Video Track, or press Ctrl+I. V1 takes video - Reversed.mkv (the scene being revealed), V2 takes wiper-video.mp4. Playback stutters badly here; Ben notes that proxy files would fix it and deliberately skips them for this tutorial.
“I’m basically going to choose as the wiper and I think I’m going to choose this one here… I’m again going to create add another split there, all I’m doing is pressing the letter s.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list. Scrub back until the area behind the chosen pillar is not yet exposed and press S. Scrub forward until the pillar has fully left frame and press S again. What sits between those two splits is the only part that needs cutting out by hand — which is why choosing the split points carefully is worth the minute it takes.
“All I’m going to do is select Ctrl C to save it on the clipboard, click source and just the little segment of this entire video is on the preview screen.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list. Exactly the same move as the door: Ctrl+C, then the Source tab. Play it through in the Source player and confirm it is only the sliver — the surrounding footage is visible on the timeline but is not what is loaded. The segment here is 00:00:04:07 long.
“Oh, almost made a mistake. So this thing here it says from timeline and that’s not where we want to pull the stills from. We want to pull the stills from the source.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list. Export → stills → PNG again, then Advanced → From → Source. The setting does not persist from the first export — it is back on Timeline and Ben catches it on screen. The export is named mask.
“Okay, took 14 seconds. Okay so now we can go into the folder and look for one’s labeled mask. As you can see here it created 28 individual images.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list. The Jobs panel shows the job at 00:00:14 for C:\Users\dasro\Desktop\Mask Transition\mask.png, and Explorer lists mask-00001 through mask-00028 at roughly 3.5 MB each. Behind the dialog the timeline reads wiper-video.mp4 on V2 over video - Reversed.mkv on V1.
“I don’t know I didn’t put it in order but let’s go to the first one here. Actually I don’t need to edit that because nothing is really showing up so I can actually close that out.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list. Drag all 28 in, then look before cutting: the first frame has no wiper in it at all, so it is closed without being touched. For the rest it is the same three moves — double-click Background to get Layer 0, select the area the pillar should hide, Delete, Ctrl+S. The rest is fast-forwarded again.
“So what I’m going to do is I’m going to add another track on top of that just so I can have a place to work with and then I’m going to go open file, I’m going to go and find the ones that start with mask.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list. Add an empty V3 as a working track, then Open File on mask-00001.png — the first of the series — and tick Image sequence in Properties exactly as before. The Open File dialog here is showing the cut PNG thumbnails, most of which are mostly transparent.
“With that on the preview screen we’re just going to click and drag it right here on this new track that I just added… you’re not going to see anything because the old file is still in the way so let’s delete that.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list, and the one place the order matters. Overlaying the cut clip on V3 shows nothing, because the uncut original on V2 is still sitting between it and the reveal. Delete the original segment first, then move the cut clip into the gap it leaves.
“I’m just going to click YouTube as a starting point and then I’m going to upgrade that to 75%. Export mask final, save.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list. Preset Stock → YouTube, Format mp4, Codec h264_amf, Rate control Quality-based VBR, GOP 15 frames, B frames 2, Codec threads 0. The Quality field is visible at 55 % mid-edit; the 75 % he raises it to is spoken but never shown on screen, so 55 % is the last verified value. The file is named mask final.
“And there you have it. This is the mask wipe transition… if you’re trying to attain a certain effect and you really need that in your video then it becomes a labor of love and so it just becomes worth it.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list. The finished wipe playing full frame: the pillar crosses, and the scene behind it has changed. Ben is straight about the cost — the door sliver alone took him thirty minutes — and equally straight that a pre-keyed green screen source would have skipped all of it.
“Every video on my channel was done on Shotcut, so aside from examples of what Shotcut can do you can also visit my playlist of tips and tutorials all geared toward the beginner.”
Derived — this card is not one of the video’s own chapters; past the end of the chapter list. End card and a pointer to the Shotcut Tips and Tricks playlist, which is where the rest of these companion pages come from.
Every step says which application you should be in. Every number below was read off the frames of the video — nothing here is a recommended-sounding guess, and where a value was spoken but never shown on screen it says so.
Before anything else, look for a version of your wiper or door footage that already ships green screened. If you find one, you are on route A and the whole job is one filter. If you do not, you are on route B and you are cutting every frame by hand. Ben says this twice, in both halves of the video, and it is the single highest-value decision here.
The two routes diverge here and never meet again. Route A is steps 2 to 4. Route B is steps 5 to 14.
Drop the reveal video on V1 and the pre-keyed clip on V2. Add the second track with a right-click on the track head, Track Operations → Add Video Track, or Ctrl+I.
Track order is not a preference. The clip that needs the hole must be the one on top.
Select the top clip, open Filters, press +, and choose Chroma Key: Simple. On this footage the green disappears immediately, because the filter already defaults to green.
Neither value is changed anywhere in the video. If your key colour is not the default green, use the eyedropper beside the swatch and click the coloured area in the preview. Raise Distance only if the key is leaving fringes; too high and it starts eating the subject.
Shorten the top clip so the reveal lands where you want it, and play it through. That is the whole of route A.
Reveal video on V1, un-keyed wiper or door video on V2. Nothing shows through yet, which is correct — there is nothing for a key to remove.
The clip Properties read H.264 / AVC, 1920x1080, 23.976024, yuv420p, ITU-R BT.709, Progressive, Broadcast Limited (MPEG).
Park the playhead where the hole first has to appear and press S. Park it where the hole is no longer needed and press S again. Only what sits between those two splits gets exported.
Every frame between the splits is a frame you will cut by hand later, so be deliberate. The door needed 34 frames; the pillar wipe needed 28.
With the segment selected press Ctrl+C, then click the Source tab under the player (next to Project). Play it through and confirm the player holds only that segment.
Skipping this is what makes the next step export the whole timeline instead of your selection.
Open Export. Scroll the preset tree to the bottom, open the stills group and choose PNG. Press Advanced and change From from Timeline to Source. Then Export File and give the series a name.
PNG and TGA are the only formats in the stills group that carry an alpha channel, and alpha is the entire point — pick JPEG here and there is nothing to make transparent. From does not stay on Source between exports; it reverts to Timeline and has to be set again every time.
The Jobs panel shows the export running. In the folder you will find the series numbered with five digits, starting at 00001.
The door export took about seven seconds; the wipe export showed 00:00:14 in the Jobs panel.
Select all the numbered files and drag them onto Photoshop. Each opens as its own tab. Any editor that can save a transparent PNG will do this job — that capability, not the brand, is the requirement.
The canvas already matches the project, so nothing needs resizing, cropping or re-saving at a different size. The exact Photoshop version is never shown on screen; the interface on screen is the CS Live-era layout.
Double-click the layer called Background in the layers panel and accept the name Layer 0. A background layer cannot hold transparency, so Delete on it fills with the background colour instead of cutting a hole.
This is the step most often skipped, and the failure is quiet: the area turns white or black instead of transparent, and you only find out when you reassemble the sequence in Shotcut.
Take the Polygonal Lasso Tool and click your way around the area that should become see-through — the open part of the doorway, or the strip the wiper object should hide. Then press Delete. Checkerboard means transparent.
Polarity, and get this the right way round: the part you delete is the part the track underneath will show through. The part you leave stays opaque and keeps hiding the track underneath. There is no black-and-white mask image in this workflow — the mask is the alpha channel of the PNG itself, so what looks like nothing on screen is doing the work.
Add a new layer, drag it below Layer 0, and Edit → Fill it with a colour nothing in your frame contains — Ben uses red. Anything pale still showing against it is selection you missed. Cut those, then delete the coloured layer before saving.
Delete the coloured layer before you save. If it is still there it is not transparent, it is red, and the effect will show a red band in Shotcut.
Ctrl+S. No Save As, no flatten, no format change — it is already a PNG and saving in place keeps the alpha and keeps the filename in the numbered series. Close the tab and move to the next frame.
The numbering is what lets Shotcut reassemble the series, so never rename a frame. If a frame has nothing to cut — the wipe sequence has one — close it without saving.
Open File and choose the first file of the series. The player shows a single still. Open Properties and tick Image sequence. Shotcut reads the whole numbered series as one clip.
00:00:01:10 at 23.976024 fps is 34 frames — exactly the number that was exported, which is the quickest way to confirm the whole series was picked up and nothing was missed.
Delete the original segment from the top track, then drag the image-sequence clip into the gap it leaves. If you overlay it on a spare track without removing the original first, nothing changes — the un-cut clip is still in the way.
The wipe build adds an empty V3 as a scratch track first, then deletes the original on V2 and moves the cut clip down into its place.
Export → preset Stock → YouTube, then Export File.
The Quality field is on screen at 55 % while Ben says he is raising it to 75 %. The raised figure never appears on screen, so 55 % is what is recorded in the table below and 75 % is recorded as spoken only. h264_amf is a hardware encoder specific to that machine’s graphics card; on other hardware the preset picks a different codec and that is fine.
Read directly off the frames. Values that were spoken but never shown on screen are labelled as such and are not presented as verified.
| Setting | Value | Where it lives |
|---|---|---|
| Shotcut version | 21.02.27 | Help → About Shotcut |
| Build copyright | © 2011-2021 Meltytech, LLC | About Shotcut dialog |
| Licence | GNU General Public License v3.0 | About Shotcut dialog |
| Project resolution | 1920 × 1080 | Clip Properties |
| Project frame rate | 23.976024 fps | Clip Properties |
| Scan mode / colour | Progressive · yuv420p · ITU-R BT.709 · Broadcast Limited (MPEG) | Clip Properties |
| Playlist item 1 | waterfalls.mp4 · 00:00:36:08 | Playlist |
| Playlist item 2 | Stairs - 65860.mp4 · 00:00:10:00 | Playlist |
| Route A track stack | V2 Stairs - 65860.mp4 / V1 waterfalls.mp4 | Timeline |
| Route B door track stack | V2 door-open-no-green01.mp4 / V1 waterfalls.mp4 | Timeline |
| Route B wipe track stack | V3 working track / V2 wiper-video.mp4 / V1 video - Reversed.mkv | Timeline |
| Only filter used, whole video | Chroma Key: Simple | Route A top clip only |
| Key color | Green, filter default (eyedropper beside the swatch to re-sample) | Chroma Key: Simple |
| Distance | 28.8 % (default, never changed) | Chroma Key: Simple |
| Add a video track | Right-click track head → Track Operations → Add Video Track, or Ctrl+I | Timeline |
| Split a clip | S, or the split button on the timeline toolbar | Timeline |
| Send a selection to the player | Ctrl+C, then the Source tab (beside Project) | Player tabs |
| Setting | Value | Where it lives |
|---|---|---|
| Preset | stills → PNG | Export preset tree |
| Other stills presets present | BMP, DPX, JPEG, PPM, TGA, TIFF | Export preset tree |
| Why PNG | Alpha channel; PNG and TGA are the only alpha-capable entries in the group | — |
| From | Timeline → Source (reverts to Timeline on every new export) | Export → Advanced |
| Format | image2 | Export → Advanced |
| Resolution | 1920 × 1080 | Advanced → Video |
| Aspect ratio | 16 : 9 | Advanced → Video |
| Frames/sec | 23.976024 | Advanced → Video |
| Scan mode | Progressive · Field order None | Advanced → Video |
| Deinterlacer | YADIF - temporal + spatial | Advanced → Video |
| Interpolation | Bilinear (good) | Advanced → Video |
| Use preview scaling | Unchecked | Advanced → Video |
| Parallel processing | Checked | Advanced → Video |
| Use hardware encoder | Checked | Export |
| Door series name / count | door-open-00001 … door-open-00034 · 34 files | Output folder |
| Wipe series name / count | mask-00001 … mask-00028 · 28 files, approx 3.5 MB each | Output folder |
| Output folder used | C:\Users\dasro\Desktop\Mask Transition | Windows Explorer |
| Export job times | Door approx 7 s (spoken) · wipe 00:00:14 (shown in Jobs) | Jobs panel |
| Setting | Value | Where it lives |
|---|---|---|
| Application | Adobe Photoshop · exact version never shown on screen | — |
| Interface generation visible | CS Live badge, Mini Bridge button, Analysis and 3D menus | Menu bar |
| Canvas size | 1920 × 1080 (unchanged from the export) | Document tab |
| Colour mode | RGB/8 | Document tab |
| Document size | Doc: 5.93M | Status bar |
| How the files are opened | Drag the numbered PNGs onto the application, one tab per frame | — |
| First move on every frame | Double-click Background → it becomes Layer 0 | Layers panel |
| Selection tool | Polygonal Lasso Tool | Tools panel / options bar |
| Feather | 0 px | Lasso options bar |
| Anti-alias | Checked | Lasso options bar |
| Refine Edge | Greyed out — not used in this tutorial | Lasso options bar |
| Cut command | Delete (with the selection active, on Layer 0) | — |
| Polarity | Deleted area = transparent = the track underneath shows through | — |
| Kept area | Opaque = keeps hiding the track underneath | — |
| Mask carrier | The PNG alpha channel. No black/white mask image, no mask filter | — |
| Edge check technique | New layer below Layer 0, Edit → Fill with red, then delete that layer | Layers panel |
| Check layer state | Layer 0 over Layer 1 · Normal · Opacity 100% · Fill 100% | Layers panel |
| Save | Ctrl+S, straight back over the same .png — no Save As, no flatten | — |
| Frames that need no edit | Closed without saving (the wipe sequence has one) | — |
| Time actually spent | Approx 30 minutes for the 34-frame door sliver (spoken) | — |
| Setting | Value | Where it lives |
|---|---|---|
| Reopen the series | Open File → the first file of the series | Open File |
| Image sequence | Checked — reads the whole numbered series as one clip | Properties |
| Resolution reported | 1920x1080 | Properties |
| Duration reported | 00:00:01:10 (= 34 frames at 23.976024 fps) | Properties |
| Pixel aspect ratio | 1 : 1 | Properties |
| Repeat | 1 frames per picture | Properties |
| Placement | Delete the original segment first, then drop the cut clip into the gap | Timeline |
| Export preset | Stock → YouTube | Export |
| Format | mp4 | Export |
| Codec | h264_amf (hardware encoder on this machine) | Export → Codec |
| Rate control | Quality-based VBR | Export → Codec |
| Quality | 55 % shown on screen · 75 % spoken, never shown | Export → Codec |
| Quantiser readout | qp_i = qp_p = qp_b = 23 | Export → Codec |
| GOP | 15 frames · Fixed unchecked | Export → Codec |
| B frames | 2 | Export → Codec |
| Codec threads | 0 (auto) | Export → Codec |
| Save as type | mp4 (*.mp4) | Save dialog |
| Output names | door open final · mask final | Save dialog |
| Door render time | Approx 4 seconds (spoken) | — |
Two settings account for most of the failures in this workflow, and neither one announces itself. The first is From in the export dialog: it defaults to Timeline, it does not remember Source between exports, and getting it wrong exports the entire timeline as stills. The second is the Background layer in Photoshop: leave it locked and Delete fills with a colour instead of cutting a hole, and you will not find out until you reassemble the sequence.
Machine transcribed from the video audio. Spoken phrasing is left as-is; only the product, filter and shortcut names the transcriber mangled have been corrected. Every timestamp plays the video in the hero from that second.
In this tutorial, I’ll be showing you how to do two transitions.
The door open mask transition and the mask wipe transition using the same technique.
So stay tuned.
I’m just a normal person with no video editing background.
I wanted to start making YouTube videos and maybe cool transitions and effects.
I don’t really plan on being a professional video editor, so I was looking for a free,
easy to learn video editing software.
Luckily, I stumbled on Shotcut, a free open source video editing program that can do many
of the tricks you can do on more enterprise video editors like Adobe Premiere or DaVinci
Resolve.
But with a much simpler and leaner interface, thus dramatically shortening the learning
curve, it just takes using your imagination.
So let’s learn together.
This tutorial is going to be done on Shotcut version 21.02.27.
So there are two ways you can accomplish a mask transition.
Let’s first start with the door open mask transition.
I’m going to show you the easy way and the painful way of doing this.
First, the easy way.
Hopefully, you’re able to find and download an already existing green screened version
of an animation of a door being opened.
Believe me, there are already tons online to save yourself the work.
I am going to start with this animation.
As the door opens, you will see the inside of the door has already been given a flat green
color.
These types of animations have already been prepped for chroma keying.
So what is chroma keying?
It is a technique used to remove the background from a video in post editing by assigning
a color that would represent what later would be transparent or invisible, typically a green
or blue background.
So as you can see in this video, they’ve already assigned the area that would later
be transparent with a solid green color.
In this first tutorial, we’re going to start out with two clips.
The first one is the stairs video that I’ve already shown you that has already
pre-green screened once the door opens.
And the second video is a video of the waterfalls that’s going to show through once the door
has been opened.
And to get started, we’re going to need to create two tracks.
So let’s start out with the waterfalls and I’m going to put that on the bottom track.
And then I’m going to add another track on top of that.
I’m going to put the stairs video on top of it.
And so as of right now, that’s what this thing looks like.
Let’s go to the green screen part of it.
As you can see, you can’t really see the waterfalls through it yet.
And so because this one has already been pre-green screened, all we have to do is
go to the area where there’s a green screen.
Go to the filters tab, click plus.
And for this one, we’re going to choose Chroma Key: Simple.
And all of a sudden it’s transparent.
That’s because it’s already pre-chosen the color green.
But if it hasn’t, all you have to do is click the little dropper and choose
the green area, which basically you’re telling the video.
Make anything that is green or this color transparent.
So now, now that we’ve done that, let’s shorten this thing here a little bit.
I’m going to play it from the very beginning.
As you’re going up the stairs, as you remember when I first opened it,
originally it was green, but now it’s see-through.
And really, that’s all it is.
It’s one filter called Chroma Key: Simple.
You select the dropper and choose the green area.
And all of a sudden, what used to be green is now transparent.
Didn’t I tell you this was the easy version?
Well, there you go.
And what you end up with is this final video.
Now, the painfully tedious version of this tip.
Other video editors like Adobe Premiere and
DaVinci Resolve have the ability to create complex mask shapes and
selections using a pen tool or a Bezier curve within the software itself.
Unfortunately, Shotcut at this current version of this video does not.
It can create simple shapes like a square or circle, but
it cannot at this point create paths.
It can create compound shapes though, which are shapes made when you
combine two simple shapes together.
But you still cannot create complex paths.
This is where an external photo editor comes into play.
An editor specifically that can save transparent PNG files.
So first, check if your photo editor can do so
before you go into this labor intensive step.
So okay, let me show you in this second tutorial how to do the
door open mask transition the hard way.
The hard way meaning we are not starting out with a video that has
already been pre green screened.
So this is the file that we have here.
And as you can see, there’s an interior.
But what we want to do is,
when this door opens.
We want it to open into this waterfall scene, just like that other one.
But in this instance, because we don’t have a green screen,
it’s going to take a lot longer.
And so we might as well proceed because this is going to take a little bit.
So just like the previous tutorial,
I’m going to drag the waterfall video in one track.
And then I’m going to create another track on top of that.
And I’m going to drag the door open green screen right on top.
But of course, you can’t see the waterfalls yet because we’re
going to need to knock out the waterfalls.
So I’m just going to cut this up a little bit so that that’s not in the way.
Put that in here.
Zoom in and let’s say we’re going to cut it like right there.
And so these are the files that we’re going to be playing with.
And so first what we need to do in this door open video is isolate
all the frames that I’m going to need to modify.
And so that’s probably the minute the door opens wide open
and covers up the entire scene.
And so I’m going to cut it there using the little split tool or S right there.
And then I also need to do, I need to find the beginning point,
which in this instance, because the door didn’t start out being closed.
We need to work it from the very beginning.
So no need to cut here because this entire clip right here
is what we need to modify.
And the way we do this is we need to extract every single
frame of this entire video
and import into a photo editing program,
which in this instance, I’m going to be using Photoshop
and I’m going to have to modify each individual picture.
And so hopefully it’s not that many frames,
but it already looks like it’s going to be at least 40 or 50
frames that we’re going to have to extract.
So while the clip that you want to extract is selected,
all you have to do is copy it by clicking Ctrl+C
so that you can copy into the clipboard.
And once you have it on the clipboard,
you can click this source tab here.
And all of a sudden, all you have is the segment of that video
that is selected right here or what’s in the clipboard.
So while I have the source selected,
all we have to do is now export them into individual PNG files.
And in order to do that, we need to go to export.
We then need to scroll all the way to the bottom and find
the stills section here.
And of course, we’re going to need to choose PNG
because this needs to be a transparent file.
And PNG is one of the only few that can actually do
transparent images.
And then we need to go to advanced and make sure
that the from because we’re pulling it from the source
instead of the project, the from here is choosing source.
So we need to make sure that that’s source.
And then we’re then going to export the file.
I’m going to save this.
Let’s call this door open, save.
All of a sudden, the job window starts.
And what it’s doing right now is it’s breaking up this
entire video clip into individual images.
So it looks like it took about seven seconds to do it,
which is really good.
And if we look into the folder, you now see that there are
multiple door open files numbered in order.
Thankfully, there’s only 34 frames in this entire thing.
So now I need to open Photoshop.
And then I’m going to need to go into that folder and drag
every single one of these photo files into it, the 34 images.
And load it one by one until it loads all 34.
Let’s go to the very first one.
So this one here.
And I’m going to show you the gist of what I’m going to
need to do to all 34 images.
So this is the first frame of that video.
And so all I need to do is go into the selection tool
and I’m going to choose the polygon lasso tool.
I’m going to create a selection here.
Just like that.
No need to be super exact.
I’ve got 34 of these to do.
I just have a rough selection area here.
Almost done.
Yep.
Pretty much selected that area.
Let me just double click it to make sure that I remove
the background.
And then I’m going to click delete.
And all of a sudden the area that I just selected
just became transparent.
How do I know?
So if this were the top layer and I add another layer
underneath it.
I’m going to drag this layer underneath it.
I’m just going to fill it with the color.
Let’s say this red color.
Edit fill.
You’re going to see that it is transparent.
You can see right through the door.
Actually you see little white areas.
Actually that little red background is helping out a little bit.
It helps me kind of isolate the areas that I’ve kind of
under deleted, undercut.
So I’m going to make another deletion on the top one.
And it looks like I got it all covered right there.
I’m just going to throw that layer away.
I’m going to save this.
And then done.
So now I’m going to go to number two.
Once again the same thing.
Make a general selection again.
Kind of just eyeballing it.
Not really taking too much time.
But if you’re doing it you definitely want to take a little
bit more time to be more exact.
To make sure your selection is pretty accurate.
Oops missed that part there.
I’m going to come back there later and fix that.
So let’s zoom in a little bit so I can fix.
I can kind of isolate that area that I want to fix there.
Right there.
Then I’m going to delete this part here.
This little white area that I missed in the selection.
Okay.
So again I’m going to double click it.
So that background becomes layer zero.
And then click delete.
And once again I have a transparency.
And I’m done with image two.
I’m going to save that.
Now I can close that.
Now we go to image three.
So now because I’m not entirely evil and I don’t want this
video to last an hour.
I’m going to spare you the time that it took me to cut
every single one of these images.
And I’m just going to fast forward it for you.
You’re welcome.
Okay.
So now that the hard part is done let’s go back into
Shotcut.
So once again this was the timeline we were working
with.
And I’m just going to play again the area that we
extracted which is this area here.
And so after doing all that processing to all those
images in Photoshop we now have to bring those
images back into Shotcut.
And so all I need to do is go into open file.
Find the first image which was door-open-00001.
I’m going to open that.
And it’s going to preview that on the screen here.
But we did all that work to process every single one
of those PNGs.
And I don’t want to have to manually bring all of
those images back into Shotcut.
But fear not.
There’s a really easy way to bring back all those
images and combine it back into a video.
And so with this image selected we then go to
properties and all we have to do is click image
sequence.
And then all of a sudden you can see here it
combined all those PNG images back into a video.
And so all I have to do is drag this back into
the timeline.
And what I’m going to do is I’m going to remove
that area that we extracted from earlier.
And I’m going to replace it with this new video
with the cutouts that we just created.
And so the end result is this.
So now I’m going to delete this part here
because we don’t need that anymore.
And I’m going to play here.
Let me let’s cut this down the size a little bit
because we don’t really need that part either.
And so this is what the preview looks like now.
And as you can see we now have somewhat of a
rough version of the door open mask transition.
You can kind of see a little bit of white around
the edges only because I didn’t really take
the time to be more detail oriented
when I was creating the selection.
But when you’re doing these things on
your photo editor you need to make sure
that you’re a lot more exact on your edges.
Here. Let’s render this.
Get back to my default here.
Let’s call this door open final.
Four seconds pretty good.
And now this is the final video.
So essentially that’s how you do a door open
mask transition.
Now using the same technique you can also
perform a special type of mask transition
called the mask wipe transition.
In this technique you’re going to use
an object in the foreground whether it’s a tree
a person or any object to act as a wiper
to wipe away a previous scene to introduce
a new scene.
One important component of the wiper object
is that it has to span from the top
of the screen all the way to the bottom.
You don’t want any gaps because it will
not look good when you do the wipe.
Okay so now let’s do the mask wipe transition.
So for this one unfortunately we’re going to
have to do it the hard way because I don’t
have a green screen version of the wiper
video and so if from the beginning you
can find a green screen version of a
wiper video just like this one save
yourself the trouble.
Don’t go through the painful process
of having to extract these things and
then select them one by one because
it’s just going to take you forever.
The last tutorial that I showed you took
me 30 minutes just to cut out that
small sliver from the door so save
yourself the trouble if you can and
find one that’s already pre-green
screen but in this tutorial I’m going
to have to use one that is not
pre-green screened and so just like the
other two we’re going to start with two
tracks so the bottom track is going to
be the one that is going to be revealed
so this is the this is the reveal video
that is underneath the wiper video so
that goes on the bottom track I’m going
to create a new track on top of that
and if you don’t know how to create
a new track just go to just right click
the track track operations and then add
video track or Ctrl+I so I’m going to
put the wiper track right on top and so
this is the original track there and
it’s stuttering a little bit but that’s
the original that’s the original track
I should have saved myself the trouble
so that this thing runs smoother by
creating proxy files but I’m not going
to go through that for this for this
particular tutorial and if you don’t
know how to create proxy files I
actually have an existing tutorial
already and it’s going to help you in
terms of your video editing by making
the editing a lot smoother instead of
it being herky jerky kind of like the
way you see it right now but for all
intents and purposes we’re not going to
do it for this particular tutorial so
I’m just going to cut this down the
size so that they match so I’m going
to take out the the excess there and
then move them there I’m going to zoom
in a little bit and so let’s watch this
and I’m going to isolate which pillar
I’m basically going to choose as the
wiper and I think I’m going to choose
this one here and so I’m going to
back up a little bit until that area
after the pillar is not exposed and so
I’m going to cut I’m going to put a
slice there and then I’m going to play
it to the very end until the pillar
fully disappears which is right there
and I’m again going to create add
another split there all I’m doing is
pressing the letter s and so this section
here is what we’re going to be
extracting and once again just like
what I did in that previous tutorial
all I’m going to do is select
Ctrl+C to save it on the clipboard
click source and just the little
segment of this entire video is on
the preview screen and so if I go and
play it it’s only that little sliver
that is going to be selected this part
here really even though it’s showing on
the screen is not selected all I want
is this area right here that already has
an endpoint and an endpoint right so
just make sure that you keep this
screen on source which is this tab
right here and again just to repeat the
the last process that I did while the
source is selected you then go to
export and again we’re going to export
stills from it again go to the stills
section here we’re going to select
PNG again because we want transparent
files and PNG again is probably the
best file type to choose for
transparent images so while that
selected I’m going to click oh almost
made a mistake so this thing here it says
from timeline and that’s not where we
want to pull the stills from we want
to pull the stills from the source
because the source is what’s showing
on the screen here so now we can
export so I’m going to export the
file and I’m going to call this one
mask I’m going to save it the jobs window
is going to show up again it looks like
it’s going to take 12 seconds still
going
okay took 14 seconds okay so now we can
go into the folder and look for one’s
labeled mask as you can see here it
created 28 individual images if you want
to see what the images look like I’m
just spot check one double click it and
it looks like that so that’s just one
PNG image so once again we’re going to
need to go to Photoshop so with Photoshop
loaded I’m once again going to need to
drag every single one into the program
so that I can manipulate each one
let’s just wait for this thing to load
shouldn’t take too long
okay so let’s go to the first one
I don’t know I didn’t put it in order
but let’s go to the first one here
actually I don’t I don’t need to edit
that because nothing is really showing up
so I can actually close that out I can
go to the second one here and again
we’re going to double click background
just to make that into a non background
layer I’m going to make a quick selection
here again this is just going to be a
rough and dirty selection if I’m
actually working on a real project
I’m going to take my time to make
sure the selection is as accurate as
possible while that’s selected I’m going
to delete and then I’m going to save
and that’s it so I’m going to fast
forward through this process once again
and I’ll see you back in Shotcut
okay so that was fun so now we’re
back in Shotcut again and once again
we’re going to try to put together all
the images that we’ve extracted and
edited and put it right back where we
pulled it from and so if you can
remember this is the source video that
we extracted those PNG files from and
so what I’m going to do is I’m going
to add another track on top of that
just so I can have a place to work
with and then I’m going to go open
file I’m going to go and find the ones
that start with mask once again and
these are my processed files so I’m
going to choose the first one of the
series starts with zero one once again
you’re just going to see a static
image on the preview screen and what
we’re going to need to do is go to
properties once again we click
Image sequence and then we get all the
clips put back together and with that on
the preview screen we’re just going to
click and drag it right here on this
new track that I just added I’m
actually going to overlay it right on
top of the old file let’s see what that
looks like there you’re not going to see
anything because the old file is still in
the way so let’s delete that and let’s
drag this new clip where the old one
used to be let’s get rid of this one
here and now this is what the final
clip looks like and so
cut this off a little bit let’s export
support that and let’s call this mask
final
we were still on the stills here almost
made a mistake there let’s drag it back
up I’m just going to click YouTube as a
starting point and then I’m going to
upgrade that to 75% export mask final
save
let it run for a little bit it should
only take a few seconds
and there you have it
this is the mask wipe transition
now don’t let me discourage you I know
it is labor intensive when you when you
start with a video that doesn’t have a
green screen on it already but if you’re
trying to attain a certain effect and
you really need that in your video then
it becomes a labor of love and so it
just it becomes worth it so hopefully
this encourages you to experiment a
little bit more with Shotcut and let
me know if there’s some other videos
and other tutorials you’d like to see
once again I’d appreciate it if you
could subscribe to this video and
hopefully you learned a lot I definitely
have in this process so until next time
thanks for watching I just wanted to
remind you that if you haven’t yet go
visit my channel I’m sure you’ll find
tons of Shotcut related videos and
don’t forget to subscribe so that you
know when I drop a new Shotcut
related tutorial every video on my
channel was done on Shotcut so aside
from examples of what Shotcut can do
you can also visit my playlist of tips
and tutorials all geared toward the
beginner visit my Shotcut tips and
tricks playlist and learn all the tips
and tricks I’ve learned during my
journey toward video editing so once
again please subscribe and I’ll see you
next time
