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fixing msmpeg4v3 dc-scale for quantizers 24-31

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Originally committed as revision 427 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2002-04-30 01:29:29 +00:00
parent bb3debab2c
commit bb71e31757
4 changed files with 9 additions and 9 deletions
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4
libavcodec/h263dec.c
View File

@ -199,9 +199,7 @@ static int h263_decode_frame(AVCodecContext *avctx,
#endif
//fprintf(stderr,"\nFrame: %d\tMB: %d",avctx->frame_number, (s->mb_y * s->mb_width) + s->mb_x);
/* DCT & quantize */
if (s->h263_msmpeg4) {
msmpeg4_dc_scale(s);
} else if (s->h263_pred) {
if (s->h263_pred && s->msmpeg4_version!=2) {
h263_dc_scale(s);
} else {
/* default quantization values */

4
libavcodec/mpegvideo.c
View File

@ -1439,9 +1439,7 @@ static void encode_mb(MpegEncContext *s, int motion_x, int motion_y)
}
#endif
/* DCT & quantize */
if (s->h263_msmpeg4) {
msmpeg4_dc_scale(s);
} else if (s->h263_pred) {
if (s->h263_pred && s->msmpeg4_version!=2) {
h263_dc_scale(s);
} else {
/* default quantization values */

1
libavcodec/mpegvideo.h
View File

@ -490,7 +490,6 @@ void msmpeg4_encode_ext_header(MpegEncContext * s);
void msmpeg4_encode_mb(MpegEncContext * s,
DCTELEM block[6][64],
int motion_x, int motion_y);
void msmpeg4_dc_scale(MpegEncContext * s);
int msmpeg4_decode_picture_header(MpegEncContext * s);
int msmpeg4_decode_ext_header(MpegEncContext * s, int buf_size);
int msmpeg4_decode_mb(MpegEncContext *s,

9
libavcodec/msmpeg4.c
View File

@ -411,7 +411,8 @@ void msmpeg4_encode_mb(MpegEncContext * s,
}
/* strongly inspirated from MPEG4, but not exactly the same ! */
#if 0
/* identical to mpeg4 for msmpeg4v3 but not msmpeg4v2 */
void msmpeg4_dc_scale(MpegEncContext * s)
{
if (s->qscale < 5 || s->msmpeg4_version==2){
@ -420,11 +421,15 @@ void msmpeg4_dc_scale(MpegEncContext * s)
}else if (s->qscale < 9){
s->y_dc_scale = 2 * s->qscale;
s->c_dc_scale = (s->qscale + 13)>>1;
}else{
}else if(s->qscale < 25){
s->y_dc_scale = s->qscale + 8;
s->c_dc_scale = (s->qscale + 13)>>1;
}else{
s->y_dc_scale = 2 * s->qscale - 16;
s->c_dc_scale = s->qscale - 6;
}
}
#endif
/* dir = 0: left, dir = 1: top prediction */
static int msmpeg4_pred_dc(MpegEncContext * s, int n,