mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-23 12:43:46 +02:00
H.261 encoder by (Maarten Daniels <maarten dot daniels at luc dot ac dot be>)
Originally committed as revision 3643 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer
parent
d7e2f57f0e
commit
1c3990dbba
@ -59,6 +59,7 @@ void avcodec_register_all(void)
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// register_avcodec(&h264_encoder);
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#ifdef CONFIG_RISKY
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register_avcodec(&mpeg2video_encoder);
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register_avcodec(&h261_encoder);
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register_avcodec(&h263_encoder);
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register_avcodec(&h263p_encoder);
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register_avcodec(&flv_encoder);
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@ -1786,6 +1786,7 @@ extern AVCodec faac_encoder;
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extern AVCodec xvid_encoder;
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extern AVCodec mpeg1video_encoder;
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extern AVCodec mpeg2video_encoder;
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extern AVCodec h261_encoder;
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extern AVCodec h263_encoder;
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extern AVCodec h263p_encoder;
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extern AVCodec flv_encoder;
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@ -47,6 +47,7 @@ typedef struct H261Context{
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MpegEncContext s;
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int current_mba;
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int previous_mba;
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int mba_diff;
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int mtype;
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int current_mv_x;
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@ -76,11 +77,330 @@ void ff_h261_loop_filter(MpegEncContext *s){
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s->dsp.h261_loop_filter(dest_cr, uvlinesize);
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}
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int ff_h261_get_picture_format(int width, int height){
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// QCIF
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if (width == 176 && height == 144)
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return 0;
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// CIF
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else if (width == 352 && height == 288)
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return 1;
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// ERROR
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else
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return -1;
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}
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static void h261_encode_block(H261Context * h, DCTELEM * block,
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int n);
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static int h261_decode_block(H261Context *h, DCTELEM *block,
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int n, int coded);
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static int h261_decode_mb(H261Context *h);
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void ff_set_qscale(MpegEncContext * s, int qscale);
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void ff_h261_encode_picture_header(MpegEncContext * s, int picture_number){
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H261Context * h = (H261Context *) s;
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int format, coded_frame_rate, coded_frame_rate_base, temp_ref;
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int best_clock_code=1;
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int best_divisor=60;
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coded_frame_rate= 1800000;
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coded_frame_rate_base= (1000+best_clock_code)*best_divisor;
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align_put_bits(&s->pb);
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/* Update the pointer to last GOB */
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s->ptr_lastgob = pbBufPtr(&s->pb);
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put_bits(&s->pb, 20, 0x10); /* PSC */
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temp_ref= s->picture_number * (int64_t)coded_frame_rate * s->avctx->frame_rate_base /
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(coded_frame_rate_base * (int64_t)s->avctx->frame_rate);
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put_bits(&s->pb, 5, temp_ref & 0x1f); /* TemporalReference */
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put_bits(&s->pb, 1, 0); /* split screen off */
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put_bits(&s->pb, 1, 0); /* camera off */
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put_bits(&s->pb, 1, 0); /* freeze picture release off */
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format = ff_h261_get_picture_format(s->width, s->height);
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put_bits(&s->pb, 1, format); /* 0 == QCIF, 1 == CIF */
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put_bits(&s->pb, 1, 0); /* still image mode */
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put_bits(&s->pb, 1, 0); /* reserved */
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put_bits(&s->pb, 1, 0); /* no PEI */
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if(format == 0)
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h->gob_number = -1;
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else
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h->gob_number = 0;
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h->current_mba = 0;
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}
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/**
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* Encodes a group of blocks header.
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*/
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static void h261_encode_gob_header(MpegEncContext * s, int mb_line){
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H261Context * h = (H261Context *)s;
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if(ff_h261_get_picture_format(s->width, s->height) == 0){
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h->gob_number+=2; // QCIF
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}
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else{
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h->gob_number++; // CIF
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}
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put_bits(&s->pb, 16, 1); /* GBSC */
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put_bits(&s->pb, 4, h->gob_number); /* GN */
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put_bits(&s->pb, 5, s->qscale); /* GQUANT */
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put_bits(&s->pb, 1, 0); /* no GEI */
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h->current_mba = 0;
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h->previous_mba = 0;
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h->current_mv_x=0;
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h->current_mv_y=0;
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}
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void ff_h261_reorder_mb_index(MpegEncContext* s){
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/* for CIF the GOB's are fragmented in the middle of a scanline
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that's why we need to adjust the x and y index of the macroblocks */
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if(ff_h261_get_picture_format(s->width,s->height) == 1){ // CIF
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if((s->mb_x == 0 && (s->mb_y % 3 == 0) ) || (s->mb_x == 11 && ((s->mb_y -1 )% 3 == 0) ))
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h261_encode_gob_header(s,0);
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if(s->mb_x < 11 ){
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if((s->mb_y % 3) == 1 ){
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s->mb_x += 0;
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s->mb_y += 1;
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}
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else if( (s->mb_y % 3) == 2 ){
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s->mb_x += 11;
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s->mb_y -= 1;
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}
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}
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else{
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if((s->mb_y % 3) == 1 ){
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s->mb_x += 0;
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s->mb_y -= 1;
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}
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else if( (s->mb_y % 3) == 0 ){
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s->mb_x -= 11;
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s->mb_y += 1;
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}
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}
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ff_init_block_index(s);
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ff_update_block_index(s);
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/* for QCIF we don't need to reorder MB's
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there the GOB's aren't fragmented in the middle of a scanline */
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}else if(ff_h261_get_picture_format(s->width,s->height) == 0){ // QCIF
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if(s->mb_y % 3 == 0 && s->mb_x == 0)
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h261_encode_gob_header(s,0);
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}
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}
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static void h261_encode_motion(H261Context * h, int val){
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MpegEncContext * const s = &h->s;
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int sign, code;
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if(val==0){
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code = 0;
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put_bits(&s->pb,h261_mv_tab[code][1],h261_mv_tab[code][0]);
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}
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else{
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if(val > 16)
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val -=32;
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if(val < -16)
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val+=32;
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sign = val < 0;
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code = sign ? -val : val;
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put_bits(&s->pb,h261_mv_tab[code][1],h261_mv_tab[code][0]);
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put_bits(&s->pb,1,sign);
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}
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}
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static inline int get_cbp(MpegEncContext * s,
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DCTELEM block[6][64])
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{
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int i, cbp;
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cbp= 0;
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for (i = 0; i < 6; i++) {
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if (s->block_last_index[i] >= 0)
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cbp |= 1 << (5 - i);
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}
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return cbp;
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}
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void ff_h261_encode_mb(MpegEncContext * s,
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DCTELEM block[6][64],
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int motion_x, int motion_y)
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{
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H261Context * h = (H261Context *)s;
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int old_mtype, mvd, mv_diff_x, mv_diff_y, i, cbp;
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cbp = 63; // avoid warning
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mvd = 0;
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h->current_mba++;
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old_mtype = h->mtype;
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h->mtype = 0;
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if (!s->mb_intra){
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/* compute cbp */
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cbp= get_cbp(s, block);
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/* mvd indicates if this block is motion compensated */
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if(((motion_x >> 1) - h->current_mv_x != 0) || ((motion_y >> 1 ) - h->current_mv_y) != 0){
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mvd = 1;
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}
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else if((motion_x >> 1 == 0) && (motion_y >> 1 == 0)){
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mvd = 0;
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}
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else
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mvd = 1;
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if((cbp | mvd | s->dquant ) == 0) {
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/* skip macroblock */
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s->skip_count++;
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h->current_mv_x=0;
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h->current_mv_y=0;
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return;
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}
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}
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/* MB is not skipped, encode MBA */
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put_bits(&s->pb, h261_mba_bits[(h->current_mba-h->previous_mba)-1], h261_mba_code[(h->current_mba-h->previous_mba)-1]);
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/* calculate MTYPE */
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if(!s->mb_intra){
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h->mtype+=2;
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if(mvd == 1){
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h->mtype+=2;
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if(cbp!=0)
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h->mtype+=1;
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if(s->loop_filter)
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h->mtype+=3;
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}
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}
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if(s->dquant)
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h->mtype++;
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put_bits(&s->pb, h261_mtype_bits[h->mtype], h261_mtype_code[h->mtype]);
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h->mtype = h261_mtype_map[h->mtype];
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if(IS_QUANT(h->mtype)){
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ff_set_qscale(s,s->qscale+s->dquant);
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put_bits(&s->pb, 5, s->qscale);
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}
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if(IS_16X16(h->mtype)){
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mv_diff_x = (motion_x >> 1) - h->current_mv_x;
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mv_diff_y = (motion_y >> 1) - h->current_mv_y;
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h->current_mv_x = (motion_x >> 1);
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h->current_mv_y = (motion_y >> 1);
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h261_encode_motion(h,mv_diff_x);
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h261_encode_motion(h,mv_diff_y);
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}
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h->previous_mba = h->current_mba;
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if(HAS_CBP(h->mtype)){
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put_bits(&s->pb,h261_cbp_tab[cbp-1][1],h261_cbp_tab[cbp-1][0]);
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}
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for(i=0; i<6; i++) {
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/* encode each block */
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h261_encode_block(h, block[i], i);
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}
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if ( ( h->current_mba == 11 ) || ( h->current_mba == 22 ) || ( h->current_mba == 33 ) || ( !IS_16X16 ( h->mtype ) )){
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h->current_mv_x=0;
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h->current_mv_y=0;
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}
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}
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void ff_h261_encode_init(MpegEncContext *s){
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static int done = 0;
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if (!done) {
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done = 1;
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init_rl(&h261_rl_tcoeff);
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}
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s->min_qcoeff= -127;
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s->max_qcoeff= 127;
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s->y_dc_scale_table=
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s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
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}
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/**
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* encodes a 8x8 block.
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* @param block the 8x8 block
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* @param n block index (0-3 are luma, 4-5 are chroma)
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*/
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static void h261_encode_block(H261Context * h, DCTELEM * block, int n){
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MpegEncContext * const s = &h->s;
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int level, run, last, i, j, last_index, last_non_zero, sign, slevel, code;
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RLTable *rl;
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rl = &h261_rl_tcoeff;
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if (s->mb_intra) {
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/* DC coef */
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level = block[0];
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/* 255 cannot be represented, so we clamp */
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if (level > 254) {
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level = 254;
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block[0] = 254;
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}
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/* 0 cannot be represented also */
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else if (level < 1) {
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level = 1;
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block[0] = 1;
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}
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if (level == 128)
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put_bits(&s->pb, 8, 0xff);
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else
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put_bits(&s->pb, 8, level);
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i = 1;
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} else if((block[0]==1 || block[0] == -1) && (s->block_last_index[n] > -1)){
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//special case
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put_bits(&s->pb,1,1);
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put_bits(&s->pb,1,block[0]>0 ? 0 : 1 );
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i = 1;
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} else {
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i = 0;
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}
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/* AC coefs */
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last_index = s->block_last_index[n];
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last_non_zero = i - 1;
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for (; i <= last_index; i++) {
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j = s->intra_scantable.permutated[i];
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level = block[j];
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if (level) {
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run = i - last_non_zero - 1;
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last = (i == last_index);
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sign = 0;
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slevel = level;
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if (level < 0) {
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sign = 1;
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level = -level;
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}
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code = get_rl_index(rl, 0 /*no last in H.261, EOB is used*/, run, level);
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if(run==0 && level < 16)
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code+=1;
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put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
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if (code == rl->n) {
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put_bits(&s->pb, 6, run);
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assert(slevel != 0);
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if(slevel < -127){
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slevel = -127;
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}
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else if(slevel > 127){
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slevel = 127;
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}
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put_bits(&s->pb, 8, slevel & 0xff);
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} else {
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put_bits(&s->pb, 1, sign);
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}
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last_non_zero = i;
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}
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}
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if(last_index > -1){
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put_bits(&s->pb, rl->table_vlc[0][1], rl->table_vlc[0][0]);// END OF BLOCK
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}
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}
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/***********************************************/
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/* decoding */
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@ -767,6 +1087,16 @@ static int h261_decode_end(AVCodecContext *avctx)
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return 0;
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}
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AVCodec h261_encoder = {
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"h261",
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CODEC_TYPE_VIDEO,
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CODEC_ID_H261,
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sizeof(H261Context),
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MPV_encode_init,
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MPV_encode_picture,
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MPV_encode_end,
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};
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AVCodec h261_decoder = {
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"h261",
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CODEC_TYPE_VIDEO,
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@ -88,7 +88,7 @@ static int RENAME(dct_quantize)(MpegEncContext *s,
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qmat = s->q_inter_matrix16[qscale][0];
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}
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if(s->out_format == FMT_H263 && s->mpeg_quant==0){
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if((s->out_format == FMT_H263 || s->out_format == FMT_H261) && s->mpeg_quant==0){
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asm volatile(
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"movd %%"REG_a", %%mm3 \n\t" // last_non_zero_p1
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@ -279,6 +279,10 @@ void ff_init_me(MpegEncContext *s){
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c->hpel_put[2][2]= c->hpel_put[2][3]= zero_hpel;
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}
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if(s->codec_id == CODEC_ID_H261){
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c->sub_motion_search= no_sub_motion_search;
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}
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c->temp= c->scratchpad;
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}
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@ -691,6 +695,12 @@ static inline void get_limits(MpegEncContext *s, int x, int y)
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c->ymin = - y - 16;
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c->xmax = - x + s->mb_width *16;
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c->ymax = - y + s->mb_height*16;
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} else if (s->out_format == FMT_H261){
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// Search range of H261 is different from other codec standards
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c->xmin = (x > 15) ? - 15 : 0;
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c->ymin = (y > 15) ? - 15 : 0;
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c->xmax = (x < s->mb_width * 16 - 16) ? 15 : 0;
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c->ymax = (y < s->mb_height * 16 - 16) ? 15 : 0;
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} else {
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c->xmin = - x;
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c->ymin = - y;
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@ -221,6 +221,16 @@ static int hpel_motion_search(MpegEncContext * s,
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}
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#endif
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static int no_sub_motion_search(MpegEncContext * s,
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int *mx_ptr, int *my_ptr, int dmin,
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int src_index, int ref_index,
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int size, int h)
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{
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(*mx_ptr)<<=1;
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(*my_ptr)<<=1;
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return dmin;
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}
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int inline ff_get_mb_score(MpegEncContext * s, int mx, int my, int src_index,
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int ref_index, int size, int h, int add_rate)
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{
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@ -1080,6 +1080,11 @@ int MPV_encode_init(AVCodecContext *avctx)
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s->low_delay=1;
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break;
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#ifdef CONFIG_RISKY
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case CODEC_ID_H261:
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s->out_format = FMT_H261;
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avctx->delay=0;
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s->low_delay=1;
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break;
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case CODEC_ID_H263:
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if (h263_get_picture_format(s->width, s->height) == 7) {
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av_log(avctx, AV_LOG_INFO, "Input picture size isn't suitable for h263 codec! try h263+\n");
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@ -1199,6 +1204,8 @@ int MPV_encode_init(AVCodecContext *avctx)
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#ifdef CONFIG_ENCODERS
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#ifdef CONFIG_RISKY
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if (s->out_format == FMT_H261)
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ff_h261_encode_init(s);
|
||||
if (s->out_format == FMT_H263)
|
||||
h263_encode_init(s);
|
||||
if(s->msmpeg4_version)
|
||||
@ -1215,7 +1222,7 @@ int MPV_encode_init(AVCodecContext *avctx)
|
||||
if(s->codec_id==CODEC_ID_MPEG4 && s->mpeg_quant){
|
||||
s->intra_matrix[j] = ff_mpeg4_default_intra_matrix[i];
|
||||
s->inter_matrix[j] = ff_mpeg4_default_non_intra_matrix[i];
|
||||
}else if(s->out_format == FMT_H263){
|
||||
}else if(s->out_format == FMT_H263 || s->out_format == FMT_H261){
|
||||
s->intra_matrix[j] =
|
||||
s->inter_matrix[j] = ff_mpeg1_default_non_intra_matrix[i];
|
||||
}else
|
||||
@ -4127,6 +4134,8 @@ static void encode_mb(MpegEncContext *s, int motion_x, int motion_y)
|
||||
msmpeg4_encode_mb(s, s->block, motion_x, motion_y); break;
|
||||
case CODEC_ID_WMV2:
|
||||
ff_wmv2_encode_mb(s, s->block, motion_x, motion_y); break;
|
||||
case CODEC_ID_H261:
|
||||
ff_h261_encode_mb(s, s->block, motion_x, motion_y); break;
|
||||
case CODEC_ID_H263:
|
||||
case CODEC_ID_H263P:
|
||||
case CODEC_ID_FLV1:
|
||||
@ -4495,15 +4504,21 @@ static int encode_thread(AVCodecContext *c, void *arg){
|
||||
ff_init_block_index(s);
|
||||
|
||||
for(mb_x=0; mb_x < s->mb_width; mb_x++) {
|
||||
const int xy= mb_y*s->mb_stride + mb_x;
|
||||
int xy= mb_y*s->mb_stride + mb_x; // removed const, H261 needs to adjust this
|
||||
int mb_type= s->mb_type[xy];
|
||||
// int d;
|
||||
int dmin= INT_MAX;
|
||||
int dir;
|
||||
|
||||
s->mb_x = mb_x;
|
||||
s->mb_y = mb_y; // moved into loop, can get changed by H.261
|
||||
ff_update_block_index(s);
|
||||
|
||||
if(s->codec_id == CODEC_ID_H261){
|
||||
ff_h261_reorder_mb_index(s);
|
||||
xy= s->mb_y*s->mb_stride + s->mb_x;
|
||||
}
|
||||
|
||||
/* write gob / video packet header */
|
||||
#ifdef CONFIG_RISKY
|
||||
if(s->rtp_mode){
|
||||
@ -5215,6 +5230,9 @@ static void encode_picture(MpegEncContext *s, int picture_number)
|
||||
mjpeg_picture_header(s);
|
||||
break;
|
||||
#ifdef CONFIG_RISKY
|
||||
case FMT_H261:
|
||||
ff_h261_encode_picture_header(s, picture_number);
|
||||
break;
|
||||
case FMT_H263:
|
||||
if (s->codec_id == CODEC_ID_WMV2)
|
||||
ff_wmv2_encode_picture_header(s, picture_number);
|
||||
|
||||
@ -865,6 +865,12 @@ extern const uint8_t ff_h263_loop_filter_strength[32];
|
||||
|
||||
/* h261.c */
|
||||
void ff_h261_loop_filter(MpegEncContext *s);
|
||||
void ff_h261_reorder_mb_index(MpegEncContext* s);
|
||||
void ff_h261_encode_mb(MpegEncContext *s,
|
||||
DCTELEM block[6][64],
|
||||
int motion_x, int motion_y);
|
||||
void ff_h261_encode_picture_header(MpegEncContext * s, int picture_number);
|
||||
void ff_h261_encode_init(MpegEncContext *s);
|
||||
|
||||
|
||||
/* h263.c, h263dec.c */
|
||||
|
||||
@ -344,6 +344,21 @@ AVInputFormat h261_iformat = {
|
||||
.value = CODEC_ID_H261,
|
||||
};
|
||||
|
||||
#ifdef CONFIG_ENCODERS
|
||||
AVOutputFormat h261_oformat = {
|
||||
"h261",
|
||||
"raw h261",
|
||||
"video/x-h261",
|
||||
"h261",
|
||||
0,
|
||||
0,
|
||||
CODEC_ID_H261,
|
||||
raw_write_header,
|
||||
raw_write_packet,
|
||||
raw_write_trailer,
|
||||
};
|
||||
#endif //CONFIG_ENCODERS
|
||||
|
||||
AVInputFormat h263_iformat = {
|
||||
"h263",
|
||||
"raw h263",
|
||||
@ -648,6 +663,7 @@ int raw_init(void)
|
||||
av_register_input_format(&dts_iformat);
|
||||
|
||||
av_register_input_format(&h261_iformat);
|
||||
av_register_output_format(&h261_oformat);
|
||||
|
||||
av_register_input_format(&h263_iformat);
|
||||
av_register_output_format(&h263_oformat);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user