... You are not limited to *.mp4 as destination. Manually change the extension to mov and it will create a real mov file (and not a mp4 file with a mov extension as one might think).
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This is a great piece of not obvious information, which saves us time! Thank you!
An external remuxer would only be needed then for batch remuxing (useful if recording is done in chunks).
@zeredis: No need to apologize my friend, I totally feel for you!
No-one really wants to add a remuxing step in their workflow if they can avoid it. However, in order not to risk irreparable issues like the one you experienced, I think you should seriously consider recording to MKV and then remuxing to something acceptable by Vegas.
I think DEDRICK did a better job in explaining de/remuxing than I did, but I'll try again and if you still don't understand it please feel free to ask for more details.
At its simplest form a media file contains video and audio streams. These streams live inside your recorded file, which is actually a media container, with a file extension MKV, MP4, MOV, etc (they are more commonly refered to as video containers, despite them also containing other types of streams, such as audio, subtitles, etc).
Different containers have different requirements about what type & amount of streams they can hold. Here is a comprehensive list on wikipedia with video and audio requirements for the most commonly used video containers now and in the past: h
ttps://en.wikipedia.org/wiki/Comparison_of_video_container_formats
For example, the FLV format cannot hold a video stream encoded in H.265. As another example, DIVX cannot hold a video stream encoded in H.264 as it cannot hold an audio stream encoded in AAC, and so on.
MKV is the most flexible container, not only being able to wrap virtually anything but also not needing to "finalize" the wrapping process. This makes it ideal for recording, but most video-editing programs do not support it. Hence the need to convert it to whatever other format the video-editing program supports.
Simply put, remuxing is converting your file from one format to another. However, it does NOT touch the enclosed video and audio streams. It rather attempts to simply copy them into a container you tell it. Problems may arise if the destination container is not capable of holding video and/or audio streams with the specs of those in the source container. For example, if you have recorded an MKV file using H.265 encoding for the video stream, and ACC encoding for the audio stream, trying to remux it into an FLV file will fail, casue FLV cannot hold H.265 video streams.
On the plus side, if remuxing succeeds then the new file has the exact video and audio quality of the original. Also the remuxing is done in just a few seconds, since all it does is wrapping up.
Now, for the above example, if instead of remuxing from MKV to FLV you opt for a re-encoding, then you have to tell your software to actually re-encode the video stream from H.265 to a video encoding supported by FLV (say H.264). Same for the audio, but in this example we assumed AAC audio, and FLV supports that... so you tell your software to simply copy the audio from the MKV file, and re-encode the video to H.264, then wrap it along with the audio as an FLV container. This will take a lot more time than simply remuxing, due to the re-encoding of the video stream. Also, any kind of lossy re-encoding will degrade the original quality.
That's one of the reasons why one should pay attention to what video & audio encoding the recording is done, and in what container.
I hope this helps you to better understand what your options are.