Skip to main content ↑ ↓

Notice

Please note that most of the software linked on this forum is likely to be safe to use. If you are unsure, feel free to ask in the relevant topics, or send a private message to an administrator or moderator. To help curb the problems of false positives, or in the event that you do find actual malware, you can contribute through the article linked here.
Topic: Upcoming ABR vs VBR listening test (Read 7970 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

Upcoming ABR vs VBR listening test

Reply #25 –
Quote
Originally posted by Dibrom
To give an example of overall behavior now, --alt-preset <bitrate> behaves similar to something like "Vorbis -b" to where on most "normal" samples, you will get a bitrate very close to what was specified, but on difficult samples, the bitrate increases.  For example, encoding fatboy with --alt-preset 128 yields a final bitrate of ~200kbps, but on a typical pop song it might be ~130kbps.
Eh, I think I somehow missed this a little. So you already have a more flexible ABR.. How did you implement this? Did you tweak PE-algorythm or something else?
Juha Laaksonheimo
 

Upcoming ABR vs VBR listening test

Reply #26 –
Quote
Originally posted by JohnV
Eh, I think I somehow missed this a little. So you already have a more flexible ABR.. How did you implement this? Did you tweak PE-algorythm or something else?


No, I haven't really messed with anything yet outside of reimplementing most of the tweaks for the vbr mode (which are mostly related to calculated masking thresholds in various manners), back into the abr mode.  Right now it's really only hacked in there because I haven't had time to go back and do things in a more proper fashion.  Because of this, it still doesn't work in an ideal manner either... (which is why I haven't released it).  I am still working on this though and experimenting with various techniques when I have the time.. again, I know that people are waiting ... juggling all these projects simultaneously is taking its toll though on how much I can get done on any given one at a time.

I've been thinking about trying to implement instead something more like a abr/vbr hybrid for more a more bitrate controlled vbr, but I'm not quite sure how feasible or how effective it would be to really do this.  2-pass would certainly help..