Differences in audio quality of mp4 and webm?
“WebM” and “MP4” are video formats (containers), so they are containers for video and audio.
There is another format (codec) for the audio inside, so I think the sound quality will change depending on the compression rate (performance) even at the same bit rate.
In other words, if the audio formats of the “WebM” and “MP4” files created by the caller use different audio formats, it is not possible to compare them simply by the size of the bitrate.
There is also a bitrate mode, like
“CBR (constant bit rate)”,
“VBR (variable bit rate)” and
“ABR (Average Bit Rate)”
.
Generally speaking, the amount of data is specified as
“CBR” = the same in any situation
“VBR” = changes depending on the situation
“ABR” = the average of the set is specified
.
Depending on the specifications of the video conversion software used, if you compare “WebM” and “MP4”, they probably both use advanced codecs with a high compression ratio and the quality and capacity of the audio data. There may not be a big difference, but there can be a considerable difference in capacity between “CBR” and “VBR”, so you may need to be careful about this.
It is safe to specify whether your video converter supports audio “dubbing”. Then there will be no deterioration.
And I think it is better to re-encode only the video with a lower bitrate.
In the “audio bitrate much higher for webm” situation, if both use advanced audio codecs, I think the webm file is likely to have higher sound quality. However, MP4 files may not degrade to a level that can be perceived by the human ear.
The video encoding is deep so if you are unsure you can either rip the audio or use the same bitrate and lower the video bitrate for encoding.
However, even if the audio is re-encoded at the same bit rate, it may not be recognized by the human ear unless it is in a lossless compression format (a format that can fully restore the original data), but it deteriorates a bit. .Keep in mind.
