To loop a local 4K 60fps MP4 in OBS, add it to the scene as a Media Source, select the file and enable Loop. OBS plays the file again when it reaches the end, while OBS still encodes a separate outgoing live stream for YouTube.
Here, “without re-encoding” can mean you do not first convert the MP4 into another file before using it. It does not mean YouTube receives the MP4 bit-for-bit or that live encoding is skipped. The distinction matters: playback settings govern the source file, while output settings govern the broadcast.
Add the MP4 as a Media Source
Open the OBS scene you intend to send to YouTube. In the Sources dock, use + and choose Media Source. Give it a recognisable name, such as “Main 4K loop”, then browse to the MP4 on your computer. The OBS Media Sources guide lists MP4 as a supported format and describes the available playback properties.
For this workflow, use a local file rather than entering a network location. The file needs to remain available to the computer running OBS for the full broadcast. If it lives on a removable drive, avoid unplugging that drive or allowing the computer to suspend it. A source that was available during setup can still fail later if its location disappears.
When you add the source, OBS may ask whether to create a new source or reuse an existing one. Reuse is useful if the same file and settings belong in more than one scene. A new source is easier to reason about when you need a different file, playback behaviour or crop. Either choice can work; the important point is to check which source is actually present in the live scene.
You do not need to make a new pre-stream copy merely to enable looping. Keep the original file and point the Media Source at it. If you later change, move or rename the file, reopen the source properties and confirm that OBS still points to the right location.
A single MP4 is the straightforward case. If your plan is to rotate among several clips, OBS documents a separate VLC Video Source with a playlist and a Loop Playlist property. VLC must be installed for that source type to appear. For a longer explanation of the multi-file route, see how to loop a playlist in OBS for YouTube Live. A single Media Source with Loop is simpler when one file is all you need.
Enable Loop and keep the source visible
Open the Media Source properties and tick Loop. This tells OBS to replay the selected file after playback completes. It does not create a second copy of the video, join the beginning and end together, or guarantee that the transition will look seamless. The end of the clip may differ visibly or audibly from its beginning.
Next, check the Sources list in the scene. The Media Source should be enabled, and any image or colour sources intended to sit behind it should be lower in the source order. In OBS, higher sources can cover lower ones. A perfectly configured looping file can appear black or missing if another source covers it, if the source is hidden, or if the wrong scene is on air.
Keep the source visible in the scene that is actually being streamed. “Visible” here refers to the source’s eye icon and whether it is covered in the scene composition, not merely whether its properties window shows the correct filename. Confirm the picture in the main preview, and then check the preview again after changing scenes.
A loop begins again when playback reaches the end. It is not a cue to switch scenes or restart the broadcast. If the video has a long black tail, silence, or a pause at its end, those parts will recur too. Trim the source in a video editor only if the content itself needs changing; that is an editorial change, not a prerequisite conversion for OBS playback.
Decide how playback restarts
The Media Source property Restart playback when source becomes active controls what happens when that source becomes active in the current scene and visible. OBS documents that behaviour in its Media Sources reference. If you want the clip to begin at its first frame when you switch to the scene, leave the option enabled and test that transition before going live.
This setting has a different purpose from Loop. Loop handles the end of one playback; restart-on-active concerns activation of the source. Consider a two-scene example: a holding slide is live while you prepare the main scene, then you switch to the scene with the MP4. With restart enabled, activating the visible source can start from the beginning. Without it, the source may continue from its existing playback position, depending on its state.
Choose based on what viewers should see after a scene change. Restarting is useful when every return to the scene should show the opening. Continuing is preferable if the file should behave like a persistent programme and a brief scene switch should not send it back to the start. Do not assume either setting creates a seamless transition; preview the exact switch you plan to use.
OBS also offers Use hardware decoding when available. This is an optional playback setting: OBS says it uses the GPU to decode certain file types when the GPU has a suitable built-in decoder. It is not a general compatibility switch and does not configure the outgoing stream encoder. If playback stutters, you can test the setting, but treat that as a troubleshooting step rather than a guarantee that a particular computer will handle every 4K60 file smoothly.
Check the source and scene before streaming
Let the MP4 play through its ending and into the next pass while watching the OBS preview. Check that the picture appears, the audio is present at the intended level, and playback restarts. Watch for a black frame, an audible gap, a jump in brightness or a sudden change in music at the loop point. The software can repeat a file; whether the join feels natural depends on how that file was edited.
Check that the selected scene is the one you will send to YouTube. If you use a scene transition, test it with the Media Source visible. A source that is hidden in one scene may behave differently from one that remains active in another. If your broadcast uses overlays, captions or logos, check that they do not obscure key parts of the video.
Also watch OBS’s audio meters while the file plays. A moving picture does not prove that audio is routed correctly. Confirm that the intended source is reaching the stream mix, that desktop audio is not unintentionally doubled, and that any silence in the file is expected. Use headphones or a private test stream if you need to hear the actual output rather than infer it from the meters.
YouTube recommends testing before a live event and monitoring stream health. Its live encoder settings and troubleshooting guidance is the place to check current ingest recommendations and test procedures. Run a representative test with the same scene, motion and audio you expect to broadcast. A still preview at the start will not reveal a problem that only appears during fast movement or at the file’s ending.
If OBS reports that the source cannot be played, first verify the file path and that the file opens locally. If it plays but stutters, distinguish source decoding trouble from a problem sending the outgoing stream: the preview may show the former even before YouTube is involved. For broader continuity planning, streaming a YouTube playlist continuously with FFmpeg concat covers a different workflow, with different setup and maintenance considerations.
What “without re-encoding” means here
The phrase can refer to two separate operations. A pre-stream conversion changes the stored video file into a different format or set of encoding parameters. Live encoding takes the frames and audio being played in OBS and produces an outgoing stream suitable for YouTube’s ingest. Adding an MP4 as a Media Source and enabling Loop avoids requiring a separate conversion step simply to repeat the file; it does not remove the outgoing live encoding step.
That is why “no re-encoding” should not be read as “send this MP4 directly to YouTube unchanged”. The local file is a playback input to OBS. OBS must configure and use an output encoder for the live broadcast. YouTube’s ingest settings describe that outgoing stream, not instructions to alter the MP4 file before loading it. YouTube also says it transcodes incoming live streams into formats for viewers, so viewers’ playback is not a bit-for-bit copy of your source.
You may still choose to edit or convert a file for a specific reason: to correct a damaged file, trim an awkward ending, change the audio mix, or reduce the burden on a computer that struggles to decode it. Those are separate decisions. The available evidence does not establish that every 4K60 MP4 will play smoothly on every machine, nor that a given loop point will be seamless. Test the actual file on the computer and scene you will use.
This distinction is useful when diagnosing a problem. If the local preview freezes, the issue may be file decoding, computer load or the source itself. If the preview is smooth but YouTube reports poor stream health, investigate the outgoing encoder, network connection and ingest settings. Converting the MP4 may help with one kind of playback issue, but it cannot by itself fix inadequate upload capacity or a misconfigured live output.
Configure the outgoing YouTube Live stream
Set the OBS output separately from the Media Source. Choose the encoder, resolution, frame rate and bitrate for the live stream you intend YouTube to receive. For 2160p (4K) at 60 frames per second, YouTube’s current guidance lists different bitrate ranges by codec: H.264 has a 14 Mbps minimum and 50 Mbps recommended, while AV1 or H.265 has a 10 Mbps minimum and 35 Mbps recommended. These are platform ingest recommendations, not a claim about the bitrate or encoding of your local MP4.
| Outgoing codec for 2160p at 60 fps | YouTube minimum bitrate | YouTube recommended bitrate |
|---|---|---|
| H.264 | 14 Mbps | 50 Mbps |
| AV1 or H.265 | 10 Mbps | 35 Mbps |
YouTube also recommends CBR and a two-second keyframe interval, with a maximum interval of four seconds. It recommends RTMPS for sending a live stream. Check the current YouTube encoder settings and the controls available in your OBS version before the event; platform advice and software options can change.
Treat the bitrate as something your connection must sustain, not just a number to type into OBS. YouTube recommends testing upload bitrate and checking stream health. A home connection that is shared with video calls, cloud backups or other uploads may not sustain the setting reliably throughout a long broadcast. If the connection cannot support the chosen 4K output consistently, decide whether a lower output resolution is a better fit than a stream that repeatedly drops frames or loses connection.
YouTube says 4K streams use normal latency; its option to improve for low latency is unavailable at 4K. That is relevant if your channel depends on quick audience interaction, but it does not change how the MP4 loops in OBS. Keep the two decisions separate: Media Source properties govern playback, while the output tab and YouTube Live Control Room govern the broadcast.
For a channel that must keep going while your own computer is off, a local OBS setup has a practical limitation: the computer and its connection have to remain available. StreamNeo removes that particular need to keep your personal machine running by taking an uploaded video and broadcasting it to YouTube; it does not change the distinction between source playback and live output, or replace checking YouTube’s current guidance. If the computer is already your preferred control point, OBS may suit you better. If you are comparing a local machine with a cloud-based arrangement, the costs of an always-on YouTube stream on Oracle Cloud versus a home PC lays out that separate operating choice.
Before committing, compare the operating options on the pricing page. When the file and channel are ready, start free — 24-hour trial, no card.
FAQ
Does enabling Loop change or convert my MP4?
No separate conversion is needed just to make a Media Source repeat. Loop tells OBS to replay the file when playback completes; it does not promise a seamless join or mean the outgoing YouTube stream is unencoded.
Does OBS send the original 4K60 file directly to YouTube?
No. The MP4 is a source played in OBS, and OBS produces an encoded outgoing live stream. Configure that output for YouTube separately, and do not expect YouTube viewers to receive the file bit-for-bit.
Should I enable hardware decoding?
Only treat it as an optional playback setting to test if useful. OBS says it depends on a suitable GPU decoder for certain file types, and it does not replace the outgoing encoder. Check playback with your actual file rather than assuming the setting guarantees smooth 4K60 performance.
Can I loop several MP4 files this way?
For a single file, use Media Source and Loop. For a playlist, OBS documents VLC Video Source and Loop Playlist; VLC must be installed for that source to be available. Test the playlist transitions and audio before broadcasting.