Question / Help Is 'remux recording' as same as 'video format converter'?

[Nga_Phoebe_Tran]

Hi guys,
Because of wanting to edit videos by adobe piemiere before uploading to Youtube, I like to change the video format (flv format) to other ones (mp4, mkv...) that are supported by adobe premiere. Acording to my research, the 'remux recording' is somehow similar to converting this video format to other ones, but this one only converts all of the videos to mp4 ones. Is this true?
I appreciate all of your answers.

 

[carlmmii]

"Remux" is a term used to mean "convert the container, keep the actual encoding untouched".

The actual encoded data is already created using whatever h.264 codec variant was used for the initial encoding. This data is placed into what's called a "container" -- this is your .mkv, .flv, or .mp4. The container is just how the encoded data is packaged up, and includes all the extra metadata for things like timestamps, date of recording, bitrate, framerate, resolution, etc.

Remuxing just allows you to strip out the encoded data and put it into a different container, without having to go through the intensive (and lossy) process of re-encoding all of the video again.

The main reason this feature exists within OBS is because OBS encodes and records in realtime. .mkv and .flv are both formats that are well suited for this (since the relevant metadata is written along-side the encoded video), but .mp4 requires that the recording end "nicely" -- the metadata for .mp4 is only written once the full encode is complete and the final state can be determined. This means if there's any issue with the recording (inability to record a section, or the program crashes before the recording can be properly stopped), the video within the .mp4 is unrecoverable.

tl;dr Record to .mkv or .flv, remux to .mp4. Remuxing just changes the container format without re-encoding the video.

btw... fairly certain Youtube supports .mkv directly, if that makes things easier.

 

[Nga_Phoebe_Tran]

"Remux" is a term used to mean "convert the container, keep the actual encoding untouched".

The actual encoded data is already created using whatever h.264 codec variant was used for the initial encoding. This data is placed into what's called a "container" -- this is your .mkv, .flv, or .mp4. The container is just how the encoded data is packaged up, and includes all the extra metadata for things like timestamps, date of recording, bitrate, framerate, resolution, etc.

Remuxing just allows you to strip out the encoded data and put it into a different container, without having to go through the intensive (and lossy) process of re-encoding all of the video again.

The main reason this feature exists within OBS is because OBS encodes and records in realtime. .mkv and .flv are both formats that are well suited for this (since the relevant metadata is written along-side the encoded video), but .mp4 requires that the recording end "nicely" -- the metadata for .mp4 is only written once the full encode is complete and the final state can be determined. This means if there's any issue with the recording (inability to record a section, or the program crashes before the recording can be properly stopped), the video within the .mp4 is unrecoverable.

tl;dr Record to .mkv or .flv, remux to .mp4. Remuxing just changes the container format without re-encoding the video.

btw... fairly certain Youtube supports .mkv directly, if that makes things easier.

So basically, remuxing is to change the container (flv, mkv... all type of formats) but to do nothing to the encoding stuff, right? But is there any issue after remuxing related to the remuxed videos?

 

[carlmmii]

Correct, and there shouldn't be any issues. After the remux, it should behave just as if the video was originally encoded to that container format.

 

[koala]

If you're asking if you encounter some kind of quality loss if you remux a video: there is absolutely no quality loss. The actual h264-encoded video data isn't changed. It's only the envelope around the video data that's being changed with remux.

Regard the wording:
"remux" changes the container only and keeps the video data verbatim. No quality loss, no change in file size. This is what OBS does.
"recode" changes the container format and re-encodes the video data. There is a quality loss involved due to the additional encoding. This is what is usually done if you use tools like Handbrake to convert and shrink a recorded video.

 

[Nga_Phoebe_Tran]

If you're asking if you encounter some kind of quality loss if you remux a video: there is absolutely no quality loss. The actual h264-encoded video data isn't changed. It's only the envelope around the video data that's being changed with remux.

Regard the wording:
"remux" changes the container only and keeps the video data verbatim. No quality loss, no change in file size. This is what OBS does.
"recode" changes the container format and re-encodes the video data. There is a quality loss involved due to the additional encoding. This is what is usually done if you use tools like Handbrake to convert and shrink a recorded video.

Ah, I'm asking this because Adobe Premiere does not support flv format. There is a saying in OBS settings that if I use mp4 format, I cannot recover my recording after a power loss or any accident like that.