-#include "mpegvideo.h"
-#include "h261data.h"
-
-
-#define H261_MBA_VLC_BITS 9
-#define H261_MTYPE_VLC_BITS 6
-#define H261_MV_VLC_BITS 7
-#define H261_CBP_VLC_BITS 9
-#define TCOEFF_VLC_BITS 9
-
-#define MBA_STUFFING 33
-#define MBA_STARTCODE 34
-#define IS_FIL(a) ((a)&MB_TYPE_H261_FIL)
-
-/**
- * H261Context
- */
-typedef struct H261Context{
- MpegEncContext s;
-
- int current_mba;
- int previous_mba;
- int mba_diff;
- int mtype;
- int current_mv_x;
- int current_mv_y;
- int gob_number;
- int gob_start_code_skipped; // 1 if gob start code is already read before gob header is read
-}H261Context;
-
-void ff_h261_loop_filter(MpegEncContext *s){
- H261Context * h= (H261Context*)s;
- const int linesize = s->linesize;
- const int uvlinesize= s->uvlinesize;
- uint8_t *dest_y = s->dest[0];
- uint8_t *dest_cb= s->dest[1];
- uint8_t *dest_cr= s->dest[2];
-
- if(!(IS_FIL (h->mtype)))
- return;
-
- s->dsp.h261_loop_filter(dest_y , linesize);
- s->dsp.h261_loop_filter(dest_y + 8, linesize);
- s->dsp.h261_loop_filter(dest_y + 8 * linesize , linesize);
- s->dsp.h261_loop_filter(dest_y + 8 * linesize + 8, linesize);
- s->dsp.h261_loop_filter(dest_cb, uvlinesize);
- s->dsp.h261_loop_filter(dest_cr, uvlinesize);
-}
-
-static int ff_h261_get_picture_format(int width, int height){
- // QCIF
- if (width == 176 && height == 144)
- return 0;
- // CIF
- else if (width == 352 && height == 288)
- return 1;
- // ERROR
- else
- return -1;
-}
-
-static void h261_encode_block(H261Context * h, DCTELEM * block,
- int n);
-static int h261_decode_block(H261Context *h, DCTELEM *block,
- int n, int coded);
-
-void ff_h261_encode_picture_header(MpegEncContext * s, int picture_number){
- H261Context * h = (H261Context *) s;
- int format, temp_ref;
-
- align_put_bits(&s->pb);
-
- /* Update the pointer to last GOB */
- s->ptr_lastgob = pbBufPtr(&s->pb);
-
- put_bits(&s->pb, 20, 0x10); /* PSC */
-
- temp_ref= s->picture_number * (int64_t)30000 * s->avctx->time_base.num /
- (1001 * (int64_t)s->avctx->time_base.den); //FIXME maybe this should use a timestamp
- put_bits(&s->pb, 5, temp_ref & 0x1f); /* TemporalReference */
-
- put_bits(&s->pb, 1, 0); /* split screen off */
- put_bits(&s->pb, 1, 0); /* camera off */
- put_bits(&s->pb, 1, 0); /* freeze picture release off */
-
- format = ff_h261_get_picture_format(s->width, s->height);
-
- put_bits(&s->pb, 1, format); /* 0 == QCIF, 1 == CIF */
-
- put_bits(&s->pb, 1, 0); /* still image mode */
- put_bits(&s->pb, 1, 0); /* reserved */
-
- put_bits(&s->pb, 1, 0); /* no PEI */
- if(format == 0)
- h->gob_number = -1;
- else
- h->gob_number = 0;
- h->current_mba = 0;
-}
-
-/**
- * Encodes a group of blocks header.
- */
-static void h261_encode_gob_header(MpegEncContext * s, int mb_line){
- H261Context * h = (H261Context *)s;
- if(ff_h261_get_picture_format(s->width, s->height) == 0){
- h->gob_number+=2; // QCIF
- }
- else{
- h->gob_number++; // CIF
- }
- put_bits(&s->pb, 16, 1); /* GBSC */
- put_bits(&s->pb, 4, h->gob_number); /* GN */
- put_bits(&s->pb, 5, s->qscale); /* GQUANT */
- put_bits(&s->pb, 1, 0); /* no GEI */
- h->current_mba = 0;
- h->previous_mba = 0;
- h->current_mv_x=0;
- h->current_mv_y=0;
-}
-
-void ff_h261_reorder_mb_index(MpegEncContext* s){
- int index= s->mb_x + s->mb_y*s->mb_width;
-
- if(index % 33 == 0)
- h261_encode_gob_header(s,0);
-
- /* for CIF the GOB's are fragmented in the middle of a scanline
- that's why we need to adjust the x and y index of the macroblocks */
- if(ff_h261_get_picture_format(s->width,s->height) == 1){ // CIF
- s->mb_x = index % 11 ; index /= 11;
- s->mb_y = index % 3 ; index /= 3;
- s->mb_x+= 11*(index % 2); index /= 2;
- s->mb_y+= 3*index;
-
- ff_init_block_index(s);
- ff_update_block_index(s);
- }
-}
-
-static void h261_encode_motion(H261Context * h, int val){
- MpegEncContext * const s = &h->s;
- int sign, code;
- if(val==0){
- code = 0;
- put_bits(&s->pb,h261_mv_tab[code][1],h261_mv_tab[code][0]);
- }
- else{
- if(val > 15)
- val -=32;
- if(val < -16)
- val+=32;
- sign = val < 0;
- code = sign ? -val : val;
- put_bits(&s->pb,h261_mv_tab[code][1],h261_mv_tab[code][0]);
- put_bits(&s->pb,1,sign);
- }
-}
-
-static inline int get_cbp(MpegEncContext * s,
- DCTELEM block[6][64])
-{
- int i, cbp;
- cbp= 0;
- for (i = 0; i < 6; i++) {
- if (s->block_last_index[i] >= 0)
- cbp |= 1 << (5 - i);
- }
- return cbp;
-}
-void ff_h261_encode_mb(MpegEncContext * s,
- DCTELEM block[6][64],
- int motion_x, int motion_y)
-{
- H261Context * h = (H261Context *)s;
- int mvd, mv_diff_x, mv_diff_y, i, cbp;
- cbp = 63; // avoid warning
- mvd = 0;
-
- h->current_mba++;
- h->mtype = 0;
-
- if (!s->mb_intra){
- /* compute cbp */
- cbp= get_cbp(s, block);
-
- /* mvd indicates if this block is motion compensated */
- mvd = motion_x | motion_y;
-
- if((cbp | mvd | s->dquant ) == 0) {
- /* skip macroblock */
- s->skip_count++;
- h->current_mv_x=0;
- h->current_mv_y=0;
- return;
- }
- }
-
- /* MB is not skipped, encode MBA */
- put_bits(&s->pb, h261_mba_bits[(h->current_mba-h->previous_mba)-1], h261_mba_code[(h->current_mba-h->previous_mba)-1]);
-
- /* calculate MTYPE */
- if(!s->mb_intra){
- h->mtype++;
-
- if(mvd || s->loop_filter)
- h->mtype+=3;
- if(s->loop_filter)
- h->mtype+=3;
- if(cbp || s->dquant)
- h->mtype++;
- assert(h->mtype > 1);
- }
-
- if(s->dquant)
- h->mtype++;
-
- put_bits(&s->pb, h261_mtype_bits[h->mtype], h261_mtype_code[h->mtype]);
-
- h->mtype = h261_mtype_map[h->mtype];
-
- if(IS_QUANT(h->mtype)){
- ff_set_qscale(s,s->qscale+s->dquant);
- put_bits(&s->pb, 5, s->qscale);
- }
-
- if(IS_16X16(h->mtype)){
- mv_diff_x = (motion_x >> 1) - h->current_mv_x;
- mv_diff_y = (motion_y >> 1) - h->current_mv_y;
- h->current_mv_x = (motion_x >> 1);
- h->current_mv_y = (motion_y >> 1);
- h261_encode_motion(h,mv_diff_x);
- h261_encode_motion(h,mv_diff_y);
- }
-
- h->previous_mba = h->current_mba;
-
- if(HAS_CBP(h->mtype)){
- assert(cbp>0);
- put_bits(&s->pb,h261_cbp_tab[cbp-1][1],h261_cbp_tab[cbp-1][0]);
- }
- for(i=0; i<6; i++) {
- /* encode each block */
- h261_encode_block(h, block[i], i);
- }
-
- if ( ( h->current_mba == 11 ) || ( h->current_mba == 22 ) || ( h->current_mba == 33 ) || ( !IS_16X16 ( h->mtype ) )){
- h->current_mv_x=0;
- h->current_mv_y=0;
- }
-}
-
-void ff_h261_encode_init(MpegEncContext *s){
- static int done = 0;
-
- if (!done) {
- done = 1;
- init_rl(&h261_rl_tcoeff, 1);
- }
-
- s->min_qcoeff= -127;
- s->max_qcoeff= 127;
- s->y_dc_scale_table=
- s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
-}
-
-
-/**
- * encodes a 8x8 block.
- * @param block the 8x8 block
- * @param n block index (0-3 are luma, 4-5 are chroma)
- */
-static void h261_encode_block(H261Context * h, DCTELEM * block, int n){
- MpegEncContext * const s = &h->s;
- int level, run, last, i, j, last_index, last_non_zero, sign, slevel, code;
- RLTable *rl;
-
- rl = &h261_rl_tcoeff;
- if (s->mb_intra) {
- /* DC coef */
- level = block[0];
- /* 255 cannot be represented, so we clamp */
- if (level > 254) {
- level = 254;
- block[0] = 254;
- }
- /* 0 cannot be represented also */
- else if (level < 1) {
- level = 1;
- block[0] = 1;
- }
- if (level == 128)
- put_bits(&s->pb, 8, 0xff);
- else
- put_bits(&s->pb, 8, level);
- i = 1;
- } else if((block[0]==1 || block[0] == -1) && (s->block_last_index[n] > -1)){
- //special case
- put_bits(&s->pb,2,block[0]>0 ? 2 : 3 );
- i = 1;
- } else {
- i = 0;
- }
-
- /* AC coefs */
- last_index = s->block_last_index[n];
- last_non_zero = i - 1;
- for (; i <= last_index; i++) {
- j = s->intra_scantable.permutated[i];
- level = block[j];
- if (level) {
- run = i - last_non_zero - 1;
- last = (i == last_index);
- sign = 0;
- slevel = level;
- if (level < 0) {
- sign = 1;
- level = -level;
- }
- code = get_rl_index(rl, 0 /*no last in H.261, EOB is used*/, run, level);
- if(run==0 && level < 16)
- code+=1;
- put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
- if (code == rl->n) {
- put_bits(&s->pb, 6, run);
- assert(slevel != 0);
- assert(level <= 127);
- put_bits(&s->pb, 8, slevel & 0xff);
- } else {
- put_bits(&s->pb, 1, sign);
- }
- last_non_zero = i;
- }
- }
- if(last_index > -1){
- put_bits(&s->pb, rl->table_vlc[0][1], rl->table_vlc[0][0]);// END OF BLOCK
- }
-}
-
-/***********************************************/
-/* decoding */
-
-static VLC h261_mba_vlc;
-static VLC h261_mtype_vlc;
-static VLC h261_mv_vlc;
-static VLC h261_cbp_vlc;
-
-void init_vlc_rl(RLTable *rl, int use_static);
-
-static void h261_decode_init_vlc(H261Context *h){
- static int done = 0;
-
- if(!done){
- done = 1;
- init_vlc(&h261_mba_vlc, H261_MBA_VLC_BITS, 35,
- h261_mba_bits, 1, 1,
- h261_mba_code, 1, 1, 1);
- init_vlc(&h261_mtype_vlc, H261_MTYPE_VLC_BITS, 10,
- h261_mtype_bits, 1, 1,
- h261_mtype_code, 1, 1, 1);
- init_vlc(&h261_mv_vlc, H261_MV_VLC_BITS, 17,
- &h261_mv_tab[0][1], 2, 1,
- &h261_mv_tab[0][0], 2, 1, 1);
- init_vlc(&h261_cbp_vlc, H261_CBP_VLC_BITS, 63,
- &h261_cbp_tab[0][1], 2, 1,
- &h261_cbp_tab[0][0], 2, 1, 1);
- init_rl(&h261_rl_tcoeff, 1);
- init_vlc_rl(&h261_rl_tcoeff, 1);
- }
-}
-
-static int h261_decode_init(AVCodecContext *avctx){
- H261Context *h= avctx->priv_data;
- MpegEncContext * const s = &h->s;
-
- // set defaults
- MPV_decode_defaults(s);
- s->avctx = avctx;
-
- s->width = s->avctx->coded_width;
- s->height = s->avctx->coded_height;
- s->codec_id = s->avctx->codec->id;
-
- s->out_format = FMT_H261;
- s->low_delay= 1;
- avctx->pix_fmt= PIX_FMT_YUV420P;
-
- s->codec_id= avctx->codec->id;
-
- h261_decode_init_vlc(h);
-
- h->gob_start_code_skipped = 0;
-
- return 0;
-}
-
-/**
- * decodes the group of blocks header or slice header.
- * @return <0 if an error occured
- */
-static int h261_decode_gob_header(H261Context *h){
- unsigned int val;
- MpegEncContext * const s = &h->s;
-
- if ( !h->gob_start_code_skipped ){
- /* Check for GOB Start Code */
- val = show_bits(&s->gb, 15);
- if(val)
- return -1;
-
- /* We have a GBSC */
- skip_bits(&s->gb, 16);
- }
-
- h->gob_start_code_skipped = 0;
-
- h->gob_number = get_bits(&s->gb, 4); /* GN */
- s->qscale = get_bits(&s->gb, 5); /* GQUANT */
-
- /* Check if gob_number is valid */
- if (s->mb_height==18){ //cif
- if ((h->gob_number<=0) || (h->gob_number>12))
- return -1;
- }
- else{ //qcif
- if ((h->gob_number!=1) && (h->gob_number!=3) && (h->gob_number!=5))
- return -1;
- }
-
- /* GEI */
- while (get_bits1(&s->gb) != 0) {
- skip_bits(&s->gb, 8);
- }
-
- if(s->qscale==0)
- return -1;
-
- // For the first transmitted macroblock in a GOB, MBA is the absolute address. For
- // subsequent macroblocks, MBA is the difference between the absolute addresses of
- // the macroblock and the last transmitted macroblock.
- h->current_mba = 0;
- h->mba_diff = 0;
-
- return 0;
-}
-
-/**
- * decodes the group of blocks / video packet header.
- * @return <0 if no resync found
- */
-static int ff_h261_resync(H261Context *h){
- MpegEncContext * const s = &h->s;
- int left, ret;
-
- if ( h->gob_start_code_skipped ){
- ret= h261_decode_gob_header(h);
- if(ret>=0)
- return 0;
- }
- else{
- if(show_bits(&s->gb, 15)==0){
- ret= h261_decode_gob_header(h);
- if(ret>=0)
- return 0;
- }
- //ok, its not where its supposed to be ...
- s->gb= s->last_resync_gb;
- align_get_bits(&s->gb);
- left= s->gb.size_in_bits - get_bits_count(&s->gb);
-
- for(;left>15+1+4+5; left-=8){
- if(show_bits(&s->gb, 15)==0){
- GetBitContext bak= s->gb;
-
- ret= h261_decode_gob_header(h);
- if(ret>=0)
- return 0;
-
- s->gb= bak;
- }
- skip_bits(&s->gb, 8);
- }
- }
-
- return -1;
-}
-
-/**
- * decodes skipped macroblocks
- * @return 0
- */
-static int h261_decode_mb_skipped(H261Context *h, int mba1, int mba2 )
-{
- MpegEncContext * const s = &h->s;
- int i;
-
- s->mb_intra = 0;
-
- for(i=mba1; i<mba2; i++){
- int j, xy;
-
- s->mb_x= ((h->gob_number-1) % 2) * 11 + i % 11;
- s->mb_y= ((h->gob_number-1) / 2) * 3 + i / 11;
- xy = s->mb_x + s->mb_y * s->mb_stride;
- ff_init_block_index(s);
- ff_update_block_index(s);
-
- for(j=0;j<6;j++)
- s->block_last_index[j] = -1;
-
- s->mv_dir = MV_DIR_FORWARD;
- s->mv_type = MV_TYPE_16X16;
- s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
- s->mv[0][0][0] = 0;
- s->mv[0][0][1] = 0;
- s->mb_skipped = 1;
- h->mtype &= ~MB_TYPE_H261_FIL;
-
- MPV_decode_mb(s, s->block);
- }
-
- return 0;
-}
-
-static int decode_mv_component(GetBitContext *gb, int v){
- int mv_diff = get_vlc2(gb, h261_mv_vlc.table, H261_MV_VLC_BITS, 2);
-
- /* check if mv_diff is valid */
- if ( mv_diff < 0 )
- return v;
-
- mv_diff = mvmap[mv_diff];
-
- if(mv_diff && !get_bits1(gb))
- mv_diff= -mv_diff;
-
- v += mv_diff;
- if (v <=-16) v+= 32;
- else if(v >= 16) v-= 32;
-
- return v;
-}
-
-static int h261_decode_mb(H261Context *h){
- MpegEncContext * const s = &h->s;
- int i, cbp, xy;
-
- cbp = 63;
- // Read mba
- do{
- h->mba_diff = get_vlc2(&s->gb, h261_mba_vlc.table, H261_MBA_VLC_BITS, 2);
-
- /* Check for slice end */
- /* NOTE: GOB can be empty (no MB data) or exist only of MBA_stuffing */
- if (h->mba_diff == MBA_STARTCODE){ // start code
- h->gob_start_code_skipped = 1;
- return SLICE_END;
- }
- }
- while( h->mba_diff == MBA_STUFFING ); // stuffing
-
- if ( h->mba_diff < 0 ){
- if ( get_bits_count(&s->gb) + 7 >= s->gb.size_in_bits )
- return SLICE_END;
-
- av_log(s->avctx, AV_LOG_ERROR, "illegal mba at %d %d\n", s->mb_x, s->mb_y);
- return SLICE_ERROR;
- }
-
- h->mba_diff += 1;
- h->current_mba += h->mba_diff;
-
- if ( h->current_mba > MBA_STUFFING )
- return SLICE_ERROR;