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What is the "important"difference between start/stop and pause/resume methods? #195
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Are you sure that is technically possible?
Not necessarily.
Yes. |
Yes, I am sure -- you can verify so yourself. I have tested this with Firefox 73 on Windows 10. Furthermore nothing in the specification prohibits it. Whether the result of concatenating blobs across a stop-start boundary is a valid media container is of course another matter. Hint: it is not a valid media container, at least not when recording into a WebM container embedding a VP9 video track.
Not sure what you mean here? I was referring to a gap when wall clock time passes between a
Yes, I have tested this empirically after submitting this issue, so I guess I can close it. |
If the media source is non-line and being played at an Concatenating multiple WebM or other container or containerless media into a single file is possible, and the media can be played back in sequence from the discrete recordings as long as a) the length of the various recordings is known; or b) the merged file is parsed to locate the beginning and ends of the merged files, e.g., WebAudio/web-audio-api-v2#61 (comment). Yes, Re "valid" and "invalid" that depends on what the criteria is and what you are trying to achieve. |
Technically, between Is the inquiry mainly about Or are you trying to meet a specific requirement? |
I am sorry for not providing you with an answer earlier. My requirements are merely to be able to pause/resume recording while assembling a valid media container (e.g. a WebM file). To that end, I was not originally sure whether stopping and starting the recorder while continuing appending chunks to the same file would result in a valid container. My testing confirmed it does not -- the media recorder produces a header data when starting recording, and normally there is only one header in a WebM file, at as its first chunk. Pausing and resuming, in contrast, merely changes what frames are generated, I assume -- at least it does not invalidate the media container when continuing to flush chunks generated by the media recorder into it. I hope this kind of explains why I created the issue. I consider it resolved, for my part, now. I'll wait with closing it, because I hope that whoever meets the same issue can draw a satisfactory conclusion here, so if I haven't explained myself, please do tell me. |
I tried reading the descriptions of all the four methods, and between
stop
andpause
at least, I can't find any difference for someone using a MediaRecorder object -- I can pause recording and resume it or I can stop it and start it again -- in both cases there is an expected gap time-wise where the stream didn't make it into the recording, but otherwise the recordings should be identical if the blobs are concatenated into a container, no? Or doesstart
write some header information as part of the first blob(s) for some/all codec and container combinations?The text was updated successfully, but these errors were encountered: