Only transcode when source bitrate is greater than maximum

[philibuster]

I am new to Subsonic, and it's pretty neat stuff. I was looking at the transcoding options earlier, and it seems like it always transcodes if it matches the file extension. Subsonic is aware of the average bitrate of the file, so why should it waste CPU cycles and bandwidth by transcoding a low-bitrate file ino a high-bitrate file? Seems like something that could be implemented fairly easily. Thanks.

[ShadowVlican]

subsonic does not transcode files into larger files

check your log (click "about")

[philibuster]

That's not true. I like to stream in ogg format, because of the bitrate efficiency, but it always converts my low-bitrate mp3s into higher-bitrate oggs, at the maximum bitrate.

Case in point, I have a 128kbps mp3, my maximum bitrate is set to 160kbps, it converts 128kbps mp3 to 160kbps ogg. That's a waste of computing time, and does a lossy->lossy conversion.

Unless my setup is different from yours, in which case, how can I make it not do this conversion?

[bushman4]

I see what you are talking about... Subsonic is transcoding your OGG file because it is an OGG file, not to downsample it. During that transcode, it is using the bitrate limit for a new bitrate even if the source file had a bitrate below that limit already.

I think it would be a good idea if the transcoding functionality could use EITHER the bitrate limit OR the average bitrate of the source file, which ever is lower, when calculating what to use for "%b" in the transcoding setup.

I second that request. +1 I guess.

But if you were talking about pure MP3 files, Shadow is right... As it stands now, Subsonic would not upsample an MP3 that was already below the bitrate limit.

Glenn

[philibuster]

I guess what I am requesting is that there be a "player can decode" list for codecs, and only transcode if the source bitrate is greater than the max bitrate OR if it is not in the "player can decode" list. This would be a great addition, I think.

[bushman4]

Well that already exists... go into the settings for the player, and shut off transcoding for OGG or whatever is "native" to your player, and transcoding will not happen for those file types on that player.

HTH,

Glenn

[philibuster]

I guess I haven't been that clear on this.

Right now, what happens is this:
For mp3:
transcode to ogg at max_bitrate even if max_bitrate>source_bitrate

For mp3:
if bitrate>max_bitrate
transcode to ogg at max_bitrate
else
play mp3 at original bitrate

For ogg:
if bitrate>max_bitrate
transcode to ogg at max_bitrate
else
play ogg at original bitrate

The reason why I want to use ogg is because of its better sound quality at lower bitrates.