To stop OBS from stretching 4:3 videos on a 16:9 YouTube stream, select the playlist source and choose Transform → Fit to Screen. That preserves the full picture and its proportions; the trade-off is unused space on either side.
You can leave those sides as bars or fill them with a background or scene elements. Stretching fills the canvas by distorting the picture, while enlarging to crop fills more of the frame by cutting off some of the video. If your playlist mixes formats, preview the actual transitions in your OBS and VLC setup rather than assuming every item will be framed alike.
Why 4:3 looks stretched on a 16:9 canvas
Aspect ratio describes a picture's width relative to its height. A 4:3 image is narrower than a 16:9 canvas when both are the same height, so it cannot cover the wider canvas without either leaving space, being distorted, or losing some of its edges. OBS's Aspect Ratio Guide illustrates 4:3 using 640×480 and notes that 16:9 is common for computer displays and is generally expected by platforms such as YouTube.
In an always-on channel, that mismatch can be easy to miss. A scene may look fine while you are arranging it, then a file appears stretched after you have resized its source. Faces look wider, circles become ovals, and text or familiar devotional imagery may look subtly wrong. The source has not necessarily changed; it is being mapped onto a canvas with a different shape.
The direct fix is to fit the source inside the canvas rather than force it to cover every pixel. The whole 4:3 image remains visible, with space at the sides. A 16:9 output is still possible: the space belongs to the surrounding scene, not to the source video. If you need a wider visual composition, you can design around the footage rather than warp it.
It helps to distinguish two OBS settings that are easy to confuse. The Base (Canvas) Resolution is the work area where you arrange sources. The Output (Scaled) Resolution is the size sent to the stream or recording. OBS describes these roles in its Studio Overview Guide. Changing output resolution does not correct a source that has been stretched inside the canvas; first fix the source transform, then review output settings separately.
Select the playlist source
In the OBS Sources dock, click the source that plays your playlist. Make sure it is the media source you intend to fix, not a background image, a camera, or a different layer with a similar name. If your scene contains several video sources, rename them clearly before making changes; names such as “Archive playlist” and “Background loop” are easier to distinguish than several entries called “Media Source.”
A playlist can be handled by an OBS Media Source when VLC Media Player is installed. OBS explains the playlist option in its Sources Guide. That documentation establishes the feature, but it does not settle how every playlist behaves when its items have different dimensions or aspect ratios. Treat the transform as a setting to verify against your files, not as a guarantee of uniform framing from item to item.
Select the source and look at the preview before opening the transform menu. Confirm that the selected source is visible and that its outline corresponds to the video region you mean to adjust. If you select the wrong layer, a correct transform can still make the scene look worse: the background might shrink, or an overlay might move, while the 4:3 footage remains unchanged.
For a reliable check, use a representative 4:3 file and pause or start playback where its picture is visible. This gives you a clear before-and-after comparison. If the preview is small, maximise the OBS window or inspect the projector preview, but do not rely only on a thumbnail or a static source outline to judge whether the video itself is distorted.
Use Fit to Screen, not Stretch to Screen
With the playlist source selected, open its context menu and choose Transform → Fit to Screen. The Sources Guide documents this transform and its keyboard shortcut: Ctrl+F on Windows or Cmd+F on macOS. The menu is the safer choice if you are unsure which shortcut applies in your setup.
Fit to Screen scales the source to fit within the canvas while retaining its proportions. On a 16:9 canvas, a 4:3 picture therefore remains narrower than the full frame. You should see the complete image, with space to its left and right. Check a familiar object or face in the preview; if it still appears unusually wide, confirm the correct source is selected and inspect the transform again.
Do not use Stretch to Screen when preserving the 4:3 shape is your priority. Stretching forces the source to cover the canvas dimensions and warps the picture. The OBS Project says in its Aspect Ratio Guide that stretching “will warp and distort the source/image, and is generally not recommended.” Stretching can be intentional for abstract textures or material where distortion is immaterial, but it is not a proportional fix for people, text, artwork, or footage whose full composition matters.
Avoid trying to correct a source transform by changing the output resolution. If the canvas stays 16:9 and the source is stretched within it, changing the stream's output size does not restore the source's original shape. Keep the roles separate: arrange and fit the source on the canvas, then choose an output size for the stream. If you do change the base canvas, expect to check source positions and sizes again because the scene's working area has changed.
OBS also documents a Scaling/Aspect Ratio filter. It changes scaling and aspect-ratio behaviour at the source level, so it is not necessary for the ordinary case where Fit to Screen gives you the intended picture. Use it only when you have a specific reason to alter dimensions, and inspect the result in the preview. For the basic 4:3-on-16:9 problem, start with the transform before adding a filter that can make the setup harder to diagnose.
Choose side bars or a background
Once the image is fitted, decide what belongs in the side space. Black bars are a valid, straightforward choice: they make no claim about picture content, preserve the full frame, and require no extra scene elements. If the footage is archival, a recording of a service, or a simple playlist where attention should stay on the video, bars may be clearer than decoration.
Another option is a background that fills the wider canvas while leaving the 4:3 image in front. You could use a still image, a subdued colour, or a deliberately designed overlay. Keep the background behind the playlist source in the Sources dock, and make sure it does not compete with the video. If you use text, check that it remains readable and does not suggest information that is absent from the footage.
A common design is to reuse the video itself as a background, enlarged and softened, while keeping the original fitted image in front. That can occupy the side space without cutting the foreground picture. It also adds another source and another transform to maintain, so check that the background is behind the main image and that transitions do not expose a blank scene. For an overlay with a title or track information, an article on adding a Now Playing track title to a YouTube meditation stream may help you think through where scene elements sit without covering the main picture.
The simplest layout is usually the easiest to troubleshoot overnight. If the side space is not harming comprehension, leave it alone. If you add scene elements, test them at the same viewing size your audience is likely to use, including a phone-sized preview if possible. A design that looks balanced on a large monitor can crowd the actual 4:3 picture on a smaller screen.
Understand the crop-to-fill trade-off
Fitting the full picture, stretching it, and cropping it solve different problems. Fit prioritises correct proportions and complete visibility. Stretch prioritises covering the canvas but distorts the picture. Cropping prioritises a full-width composition without distortion, but hides part of the source. No single choice gives you all three: original proportions, every edge visible, and a canvas fully covered by the source.
| Choice | What happens on a 16:9 canvas | What you give up | Useful when |
|---|---|---|---|
| Fit to Screen | Keeps the full 4:3 image proportional, leaving space at the sides | The source alone does not fill the canvas | All edges and the original shape matter |
| Stretch to Screen | Forces the image to cover the canvas | Correct proportions | Distortion is acceptable for the material |
| Enlarge or crop | Keeps proportions while extending the picture beyond the canvas | Content at the edges | The centre matters more than the full frame |
| Fit plus background | Shows the full proportional image over a designed wider scene | A plain, minimal composition | You want to use side space without distorting the source |
To crop, you enlarge the source until its sides extend beyond the canvas, then position it so the important content remains visible. For a face centred in the picture, that may be workable. For subtitles, a person near the edge, a temple detail, or a title embedded in the source, the crop may remove something essential. Preview the whole source and identify what would be lost before choosing it.
Cropping and stretching are not interchangeable. Stretching retains the source's outer content but changes its shape. Cropping retains the shape of what remains but removes some content. If you are unsure, fit the source first; you can always make a deliberate crop after you have seen the complete frame.
For a broader explanation of canvas choices and common YouTube dimensions, see YouTube video aspect ratio and best sizes for live streams. Use that as context for planning a scene, not as a reason to resize every source to the same shape. A 16:9 stream can contain a correctly framed 4:3 source.
Check playlists with mixed dimensions
A playlist may include files made at different resolutions or with different aspect ratios. Those differences are not the same thing: two files can have different pixel dimensions but the same shape, or the same general resolution class but different shapes. A transform that looks right for one item does not prove that the next item will be framed as you expect.
OBS documents playlist support through a Media Source when VLC is installed, but the cited guide does not specify how transitions between different-dimension or different-aspect items will be framed in every setup. Do not promise yourself that mixed items will automatically keep consistent framing. Verify the actual playlist in the OBS/VLC configuration you plan to run.
Make a short test playlist that includes one item of each type you expect to broadcast: for example, a 4:3 recording, a 16:9 clip, and any unusual file that will be part of the rotation. Start playback and watch the preview as each item begins. Note whether the image is fitted, cropped, or distorted, and whether the scene exposes empty space while one file ends and another starts. The point is not to assume a particular transition behaviour, but to observe what your setup does.
If framing changes between items, decide what you can accept before leaving the playlist unattended. You might prepare separate scenes or sources for groups of material, normalise the files outside OBS, or retain bars and accept that the composition varies. Each method adds a different burden: scene changes require careful playlist operation, file preparation takes time, and a variable frame may look inconsistent. Choose the least fragile option for the channel rather than relying on undocumented behaviour.
This is also a good time to check audio continuity, titles, and overlays. A picture that changes shape can be a clue that the wrong item or source is active, but sound and scene elements can fail independently. For a 24/7 channel, OBS source ordering for a YouTube stream with an overlay offers related guidance on how scene layers affect what viewers see.
Preview item transitions before streaming
A static preview confirms only the current frame. Let the playlist run through an item change while you watch OBS's preview. Check the last moments of the outgoing file, the first moments of the incoming one, and the settled frame after the transition. If you use a background, overlay, or text, confirm it remains behind or around the video rather than obscuring it.
Where practical, test the playlist in a private or otherwise controlled broadcast setup before making it part of a public, unattended channel. Check the stream on YouTube as well as the OBS preview if you can: the preview tells you how the scene is arranged, while the live playback lets you confirm what reaches the platform. Consult current YouTube Help for live-streaming setup for platform instructions; requirements and interface details can change, so check the official page rather than relying on an old checklist.
Do not treat a successful first item as proof that a long playlist is ready. At minimum, include each format and source you expect to recur, and observe the transition that concerns you. If you cannot wait for a full rotation, construct a short test playlist with representative files and run that through the same scene and source configuration. Record which combinations you tested so later edits do not silently undo the framing you checked.
For an always-on stream, the computer must remain on and OBS must keep playing the playlist; a correct transform alone does not keep a broadcast running. If the recurring pain is leaving a computer on to replay a prepared file, StreamNeo removes that specific burden by turning an uploaded video into a YouTube live stream that runs with your computer switched off. It does not change the need to prepare footage with the framing you want, and it is YouTube-only.
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FAQ
How do I stop OBS from stretching 4:3 videos in a YouTube playlist?
Select the playlist source and choose Transform → Fit to Screen. Check the preview: the full picture should keep its proportions and leave space at the sides of a 16:9 canvas. Do not use Stretch to Screen if you want the original shape.
How do I keep the black bars instead of stretching the video?
Fit the source to the screen and leave the unused side space as bars. If you prefer, put a background or other scene element behind the fitted source; the video itself can remain proportional while the rest of the canvas is filled.
Will a mixed-aspect playlist keep the same framing automatically?
Do not assume that it will. OBS documents playlist support through a Media Source with VLC installed, but the cited guide does not settle framing across items with different dimensions or aspect ratios. Test each kind of file and its transition in your actual setup.
Should I change output resolution to fix the stretched picture?
Usually, no. The source transform controls how the image is arranged on the canvas, while output resolution controls the dimensions sent to the stream or recording. Fit the source first, then review the output setting separately if you have a reason to change it.