Issue
So I have an app where mp3 file is being played using the MediaPlayer
. On most devices everything is fine but on Samsung and some other (like HTC One S) devices the same mp3 plays "too fast" (skipping gaps): looks like player does not handle sound gaps (silence) correctly. These mp3s are just speech and speech naturally has gaps (silence) between spoken words. And these gaps are not played correctly in terms of time - MediaPlayer
just skips them. As result mp3 is played faster by the duration of all gaps it contains.
What could be a reason and solution for this?
UPDATE
I'd found that its about frequency+VBR. Somehow if mp3 is of 22050/24000/32000 Hz instead of 44100 or 48000 and VBR or ABR is used the issue raises up. Im using LAME for mp3 encoding. If I remove "--resample 22.05" option so the resulting mp3 becomes 44.1kHz there is no issue playing this mp3 on samsung phone. However the resulting size of mp3 becomes twice bigger which is not acceptable for me cuz in this case my apk becomes bigger than 50Mb.
So now the question is how to properly compress mp3 as 22kHz/VBR/MONO.
Solution
The issue was fixed in the following way: I added a white noise to an original sound and then encoded it to MP3 format. Resulting files became bigger in size but also they become more compatible (with Samsung devices)
The original audio file (made at recording studio) is too clean meaning that silence/pauses in speech (between pronounced words) has no waveform if look in sound editor, its like an ideal silence. So on variuos Samsung devices such MP3-encoded files played with described issue. However on most other devices and PCs such MP3 files played just fine. Once again - Samsung "rules"!
Answered By - Stan
0 comments:
Post a Comment
Note: Only a member of this blog may post a comment.