Opened 16 years ago
Last modified 13 years ago
#1263 new defect
Max framerate for SP@L3 incorrect
| Reported by: | Owned by: | reimar | |
|---|---|---|---|
| Priority: | normal | Component: | ve |
| Version: | HEAD | Severity: | normal |
| Keywords: | Cc: | ||
| Blocked By: | Blocking: | ||
| Reproduced by developer: | no | Analyzed by developer: | no |
Description
There is a table in libmpcodecs/ve_xvid4.c which specifies constraints for encoding to the various profiles and levels of MPEG-4 part 2. For Simple Profile level 2 and 3 it specifies, in part:
level 2 level 3
max resolution: 352 x 288 352 x 288
max frames/s: 15 15
max macroblocks/s: 5940 11880
This does not look right for level 3. Since 352/16 * 288/16 * 15 = 5940, the figures are correct for level 2; but surely the limit for level 3 should be 30 fps?
More generally, The MPEG-4 standard doesn't, as far as I can tell, specify any particular maximum resolution or framerate, other than in terms of macroblocks/s (VCV decoder rate). So level 2 should allow e.g. 1056 x 96 @ 15 fps = 5940 macroblocks/s.
Description of the profiles: http://www.m4if.org/resources/profiles/index.html
