[XviD-devel] Bframe bugfixes

Christoph Lampert xvid-devel@xvid.org
Mon, 22 Jul 2002 10:45:22 +0200 (CEST)


On Mon, 22 Jul 2002, Edouard Gomez wrote:

> I've tested your bugfixes and the same MB problem occurs.
> 
> This time i've made a snapshot :
> 
> http://perso.wanadoo.fr/ed.gomez/files/xinesnap-20020722-094140-1.png
> 
> You can see the wrong MBs at the bottom of the black 'O' letter.

Did you try without adaptive quantization? I didn't test with it. 
I don't know if this has any influence (from my point, it shouldn't), but
it's worth a try. 

If it's still there, try to lower the value "DIRECT_UPPERLIMIT" in 

xvidcore/src/motion/motion_est.c 

First to 0 (then it _must_ disappear, because direct mode is off), 
then to some other value. I really thought 256 would be okay, but
maybe you proved me wrong. 

The influence is not big, anyway. Simply leave it to 0 and you should not 
have too big problems. I'll add residue encoding to direct mode as soon as
possible, then these problems should be history. 

gruel

> 
> Using these settings :
> 
> [export_xvidcvs.so]     multi-pass session: 0
> [export_xvidcvs.so]                quality: 0
> [export_xvidcvs.so]      bitrate [kBits/s]: 710
> [export_xvidcvs.so]  max keyframe interval: 250
> [export_xvidcvs.so]    max bframe sequence: 1
> [export_xvidcvs.so]     bframe quant ratio: 140
> [export_xvidcvs.so]           motion flags:
>                              PMV_HALFPELREFINE16
>                              PMV_EXTSEARCH16
>                              PMV_EARLYSTOP16
>                              PMV_HALFPELREFINE8
>                              PMV_EARLYSTOP8
> [export_xvidcvs.so]           global flags:
>                              XVID_GLOBAL_DX50BVOP
> [export_xvidcvs.so]          general flags:
>                              XVID_H263QUANT
>                              XVID_HALFPEL
>                              XVID_ADAPTIVEQUANT
>                              XVID_LUMIMASKING
>                              XVID_INTER4V
> [export_xvidcvs.so]              cpu flags:
>                              XVID_CPU_MMX
>                              XVID_CPU_MMXEXT
>                              XVID_CPU_SSE
>                              XVID_CPU_TSC
> [export_xvidcvs.so]             frame rate: 25.00
> [export_xvidcvs.so]            color space: YV12
> 
> 
> -- 
> Edouard Gomez
> _______________________________________________
> XviD-devel mailing list
> XviD-devel@xvid.org
> http://list.xvid.org/mailman/listinfo/xvid-devel
> 

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