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-rw-r--r--libavcodec/snowdec.c587
1 files changed, 587 insertions, 0 deletions
diff --git a/libavcodec/snowdec.c b/libavcodec/snowdec.c
new file mode 100644
index 0000000000..c8a03277e6
--- /dev/null
+++ b/libavcodec/snowdec.c
@@ -0,0 +1,587 @@
+/*
+ * Copyright (C) 2004 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/intmath.h"
+#include "libavutil/log.h"
+#include "libavutil/opt.h"
+#include "avcodec.h"
+#include "dsputil.h"
+#include "snow_dwt.h"
+#include "internal.h"
+#include "snow.h"
+
+#include "rangecoder.h"
+#include "mathops.h"
+
+#include "mpegvideo.h"
+#include "h263.h"
+
+#undef NDEBUG
+#include <assert.h>
+
+static av_always_inline void predict_slice_buffered(SnowContext *s, slice_buffer * sb, IDWTELEM * old_buffer, int plane_index, int add, int mb_y){
+ Plane *p= &s->plane[plane_index];
+ const int mb_w= s->b_width << s->block_max_depth;
+ const int mb_h= s->b_height << s->block_max_depth;
+ int x, y, mb_x;
+ int block_size = MB_SIZE >> s->block_max_depth;
+ int block_w = plane_index ? block_size>>s->chroma_h_shift : block_size;
+ int block_h = plane_index ? block_size>>s->chroma_v_shift : block_size;
+ const uint8_t *obmc = plane_index ? ff_obmc_tab[s->block_max_depth+s->chroma_h_shift] : ff_obmc_tab[s->block_max_depth];
+ int obmc_stride= plane_index ? (2*block_size)>>s->chroma_h_shift : 2*block_size;
+ int ref_stride= s->current_picture.linesize[plane_index];
+ uint8_t *dst8= s->current_picture.data[plane_index];
+ int w= p->width;
+ int h= p->height;
+
+ if(s->keyframe || (s->avctx->debug&512)){
+ if(mb_y==mb_h)
+ return;
+
+ if(add){
+ for(y=block_h*mb_y; y<FFMIN(h,block_h*(mb_y+1)); y++){
+// DWTELEM * line = slice_buffer_get_line(sb, y);
+ IDWTELEM * line = sb->line[y];
+ for(x=0; x<w; x++){
+// int v= buf[x + y*w] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
+ int v= line[x] + (128<<FRAC_BITS) + (1<<(FRAC_BITS-1));
+ v >>= FRAC_BITS;
+ if(v&(~255)) v= ~(v>>31);
+ dst8[x + y*ref_stride]= v;
+ }
+ }
+ }else{
+ for(y=block_h*mb_y; y<FFMIN(h,block_h*(mb_y+1)); y++){
+// DWTELEM * line = slice_buffer_get_line(sb, y);
+ IDWTELEM * line = sb->line[y];
+ for(x=0; x<w; x++){
+ line[x] -= 128 << FRAC_BITS;
+// buf[x + y*w]-= 128<<FRAC_BITS;
+ }
+ }
+ }
+
+ return;
+ }
+
+ for(mb_x=0; mb_x<=mb_w; mb_x++){
+ add_yblock(s, 1, sb, old_buffer, dst8, obmc,
+ block_w*mb_x - block_w/2,
+ block_h*mb_y - block_h/2,
+ block_w, block_h,
+ w, h,
+ w, ref_stride, obmc_stride,
+ mb_x - 1, mb_y - 1,
+ add, 0, plane_index);
+ }
+}
+
+static inline void decode_subband_slice_buffered(SnowContext *s, SubBand *b, slice_buffer * sb, int start_y, int h, int save_state[1]){
+ const int w= b->width;
+ int y;
+ const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
+ int qmul= ff_qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
+ int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
+ int new_index = 0;
+
+ if(b->ibuf == s->spatial_idwt_buffer || s->qlog == LOSSLESS_QLOG){
+ qadd= 0;
+ qmul= 1<<QEXPSHIFT;
+ }
+
+ /* If we are on the second or later slice, restore our index. */
+ if (start_y != 0)
+ new_index = save_state[0];
+
+
+ for(y=start_y; y<h; y++){
+ int x = 0;
+ int v;
+ IDWTELEM * line = slice_buffer_get_line(sb, y * b->stride_line + b->buf_y_offset) + b->buf_x_offset;
+ memset(line, 0, b->width*sizeof(IDWTELEM));
+ v = b->x_coeff[new_index].coeff;
+ x = b->x_coeff[new_index++].x;
+ while(x < w){
+ register int t= ( (v>>1)*qmul + qadd)>>QEXPSHIFT;
+ register int u= -(v&1);
+ line[x] = (t^u) - u;
+
+ v = b->x_coeff[new_index].coeff;
+ x = b->x_coeff[new_index++].x;
+ }
+ }
+
+ /* Save our variables for the next slice. */
+ save_state[0] = new_index;
+
+ return;
+}
+
+static int decode_q_branch(SnowContext *s, int level, int x, int y){
+ const int w= s->b_width << s->block_max_depth;
+ const int rem_depth= s->block_max_depth - level;
+ const int index= (x + y*w) << rem_depth;
+ int trx= (x+1)<<rem_depth;
+ const BlockNode *left = x ? &s->block[index-1] : &null_block;
+ const BlockNode *top = y ? &s->block[index-w] : &null_block;
+ const BlockNode *tl = y && x ? &s->block[index-w-1] : left;
+ const BlockNode *tr = y && trx<w && ((x&1)==0 || level==0) ? &s->block[index-w+(1<<rem_depth)] : tl; //FIXME use lt
+ int s_context= 2*left->level + 2*top->level + tl->level + tr->level;
+ int res;
+
+ if(s->keyframe){
+ set_blocks(s, level, x, y, null_block.color[0], null_block.color[1], null_block.color[2], null_block.mx, null_block.my, null_block.ref, BLOCK_INTRA);
+ return 0;
+ }
+
+ if(level==s->block_max_depth || get_rac(&s->c, &s->block_state[4 + s_context])){
+ int type, mx, my;
+ int l = left->color[0];
+ int cb= left->color[1];
+ int cr= left->color[2];
+ int ref = 0;
+ int ref_context= av_log2(2*left->ref) + av_log2(2*top->ref);
+ int mx_context= av_log2(2*FFABS(left->mx - top->mx)) + 0*av_log2(2*FFABS(tr->mx - top->mx));
+ int my_context= av_log2(2*FFABS(left->my - top->my)) + 0*av_log2(2*FFABS(tr->my - top->my));
+
+ type= get_rac(&s->c, &s->block_state[1 + left->type + top->type]) ? BLOCK_INTRA : 0;
+
+ if(type){
+ pred_mv(s, &mx, &my, 0, left, top, tr);
+ l += get_symbol(&s->c, &s->block_state[32], 1);
+ cb+= get_symbol(&s->c, &s->block_state[64], 1);
+ cr+= get_symbol(&s->c, &s->block_state[96], 1);
+ }else{
+ if(s->ref_frames > 1)
+ ref= get_symbol(&s->c, &s->block_state[128 + 1024 + 32*ref_context], 0);
+ if (ref >= s->ref_frames) {
+ av_log(s->avctx, AV_LOG_ERROR, "Invalid ref\n");
+ return AVERROR_INVALIDDATA;
+ }
+ pred_mv(s, &mx, &my, ref, left, top, tr);
+ mx+= get_symbol(&s->c, &s->block_state[128 + 32*(mx_context + 16*!!ref)], 1);
+ my+= get_symbol(&s->c, &s->block_state[128 + 32*(my_context + 16*!!ref)], 1);
+ }
+ set_blocks(s, level, x, y, l, cb, cr, mx, my, ref, type);
+ }else{
+ if ((res = decode_q_branch(s, level+1, 2*x+0, 2*y+0)) < 0 ||
+ (res = decode_q_branch(s, level+1, 2*x+1, 2*y+0)) < 0 ||
+ (res = decode_q_branch(s, level+1, 2*x+0, 2*y+1)) < 0 ||
+ (res = decode_q_branch(s, level+1, 2*x+1, 2*y+1)) < 0)
+ return res;
+ }
+ return 0;
+}
+
+static void dequantize_slice_buffered(SnowContext *s, slice_buffer * sb, SubBand *b, IDWTELEM *src, int stride, int start_y, int end_y){
+ const int w= b->width;
+ const int qlog= av_clip(s->qlog + b->qlog, 0, QROOT*16);
+ const int qmul= ff_qexp[qlog&(QROOT-1)]<<(qlog>>QSHIFT);
+ const int qadd= (s->qbias*qmul)>>QBIAS_SHIFT;
+ int x,y;
+
+ if(s->qlog == LOSSLESS_QLOG) return;
+
+ for(y=start_y; y<end_y; y++){
+// DWTELEM * line = slice_buffer_get_line_from_address(sb, src + (y * stride));
+ IDWTELEM * line = slice_buffer_get_line(sb, (y * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
+ for(x=0; x<w; x++){
+ int i= line[x];
+ if(i<0){
+ line[x]= -((-i*qmul + qadd)>>(QEXPSHIFT)); //FIXME try different bias
+ }else if(i>0){
+ line[x]= (( i*qmul + qadd)>>(QEXPSHIFT));
+ }
+ }
+ }
+}
+
+static void correlate_slice_buffered(SnowContext *s, slice_buffer * sb, SubBand *b, IDWTELEM *src, int stride, int inverse, int use_median, int start_y, int end_y){
+ const int w= b->width;
+ int x,y;
+
+ IDWTELEM * line=0; // silence silly "could be used without having been initialized" warning
+ IDWTELEM * prev;
+
+ if (start_y != 0)
+ line = slice_buffer_get_line(sb, ((start_y - 1) * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
+
+ for(y=start_y; y<end_y; y++){
+ prev = line;
+// line = slice_buffer_get_line_from_address(sb, src + (y * stride));
+ line = slice_buffer_get_line(sb, (y * b->stride_line) + b->buf_y_offset) + b->buf_x_offset;
+ for(x=0; x<w; x++){
+ if(x){
+ if(use_median){
+ if(y && x+1<w) line[x] += mid_pred(line[x - 1], prev[x], prev[x + 1]);
+ else line[x] += line[x - 1];
+ }else{
+ if(y) line[x] += mid_pred(line[x - 1], prev[x], line[x - 1] + prev[x] - prev[x - 1]);
+ else line[x] += line[x - 1];
+ }
+ }else{
+ if(y) line[x] += prev[x];
+ }
+ }
+ }
+}
+
+static void decode_qlogs(SnowContext *s){
+ int plane_index, level, orientation;
+
+ for(plane_index=0; plane_index<3; plane_index++){
+ for(level=0; level<s->spatial_decomposition_count; level++){
+ for(orientation=level ? 1:0; orientation<4; orientation++){
+ int q;
+ if (plane_index==2) q= s->plane[1].band[level][orientation].qlog;
+ else if(orientation==2) q= s->plane[plane_index].band[level][1].qlog;
+ else q= get_symbol(&s->c, s->header_state, 1);
+ s->plane[plane_index].band[level][orientation].qlog= q;
+ }
+ }
+ }
+}
+
+#define GET_S(dst, check) \
+ tmp= get_symbol(&s->c, s->header_state, 0);\
+ if(!(check)){\
+ av_log(s->avctx, AV_LOG_ERROR, "Error " #dst " is %d\n", tmp);\
+ return -1;\
+ }\
+ dst= tmp;
+
+static int decode_header(SnowContext *s){
+ int plane_index, tmp;
+ uint8_t kstate[32];
+
+ memset(kstate, MID_STATE, sizeof(kstate));
+
+ s->keyframe= get_rac(&s->c, kstate);
+ if(s->keyframe || s->always_reset){
+ ff_snow_reset_contexts(s);
+ s->spatial_decomposition_type=
+ s->qlog=
+ s->qbias=
+ s->mv_scale=
+ s->block_max_depth= 0;
+ }
+ if(s->keyframe){
+ GET_S(s->version, tmp <= 0U)
+ s->always_reset= get_rac(&s->c, s->header_state);
+ s->temporal_decomposition_type= get_symbol(&s->c, s->header_state, 0);
+ s->temporal_decomposition_count= get_symbol(&s->c, s->header_state, 0);
+ GET_S(s->spatial_decomposition_count, 0 < tmp && tmp <= MAX_DECOMPOSITIONS)
+ s->colorspace_type= get_symbol(&s->c, s->header_state, 0);
+ s->chroma_h_shift= get_symbol(&s->c, s->header_state, 0);
+ s->chroma_v_shift= get_symbol(&s->c, s->header_state, 0);
+
+ if(s->chroma_h_shift == 1 && s->chroma_v_shift==1){
+ s->avctx->pix_fmt= AV_PIX_FMT_YUV420P;
+ }else if(s->chroma_h_shift == 0 && s->chroma_v_shift==0){
+ s->avctx->pix_fmt= AV_PIX_FMT_YUV444P;
+ }else if(s->chroma_h_shift == 2 && s->chroma_v_shift==2){
+ s->avctx->pix_fmt= AV_PIX_FMT_YUV410P;
+ } else {
+ av_log(s, AV_LOG_ERROR, "unsupported color subsample mode %d %d\n", s->chroma_h_shift, s->chroma_v_shift);
+ s->chroma_h_shift = s->chroma_v_shift = 1;
+ s->avctx->pix_fmt= AV_PIX_FMT_YUV420P;
+ return AVERROR_INVALIDDATA;
+ }
+
+ s->spatial_scalability= get_rac(&s->c, s->header_state);
+// s->rate_scalability= get_rac(&s->c, s->header_state);
+ GET_S(s->max_ref_frames, tmp < (unsigned)MAX_REF_FRAMES)
+ s->max_ref_frames++;
+
+ decode_qlogs(s);
+ }
+
+ if(!s->keyframe){
+ if(get_rac(&s->c, s->header_state)){
+ for(plane_index=0; plane_index<2; plane_index++){
+ int htaps, i, sum=0;
+ Plane *p= &s->plane[plane_index];
+ p->diag_mc= get_rac(&s->c, s->header_state);
+ htaps= get_symbol(&s->c, s->header_state, 0)*2 + 2;
+ if((unsigned)htaps > HTAPS_MAX || htaps==0)
+ return -1;
+ p->htaps= htaps;
+ for(i= htaps/2; i; i--){
+ p->hcoeff[i]= get_symbol(&s->c, s->header_state, 0) * (1-2*(i&1));
+ sum += p->hcoeff[i];
+ }
+ p->hcoeff[0]= 32-sum;
+ }
+ s->plane[2].diag_mc= s->plane[1].diag_mc;
+ s->plane[2].htaps = s->plane[1].htaps;
+ memcpy(s->plane[2].hcoeff, s->plane[1].hcoeff, sizeof(s->plane[1].hcoeff));
+ }
+ if(get_rac(&s->c, s->header_state)){
+ GET_S(s->spatial_decomposition_count, 0 < tmp && tmp <= MAX_DECOMPOSITIONS)
+ decode_qlogs(s);
+ }
+ }
+
+ s->spatial_decomposition_type+= get_symbol(&s->c, s->header_state, 1);
+ if(s->spatial_decomposition_type > 1U){
+ av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_type %d not supported\n", s->spatial_decomposition_type);
+ return -1;
+ }
+ if(FFMIN(s->avctx-> width>>s->chroma_h_shift,
+ s->avctx->height>>s->chroma_v_shift) >> (s->spatial_decomposition_count-1) <= 1){
+ av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_count %d too large for size\n", s->spatial_decomposition_count);
+ return -1;
+ }
+
+
+ s->qlog += get_symbol(&s->c, s->header_state, 1);
+ s->mv_scale += get_symbol(&s->c, s->header_state, 1);
+ s->qbias += get_symbol(&s->c, s->header_state, 1);
+ s->block_max_depth+= get_symbol(&s->c, s->header_state, 1);
+ if(s->block_max_depth > 1 || s->block_max_depth < 0){
+ av_log(s->avctx, AV_LOG_ERROR, "block_max_depth= %d is too large\n", s->block_max_depth);
+ s->block_max_depth= 0;
+ return -1;
+ }
+
+ return 0;
+}
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+ int ret;
+
+ if ((ret = ff_snow_common_init(avctx)) < 0) {
+ ff_snow_common_end(avctx->priv_data);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int decode_blocks(SnowContext *s){
+ int x, y;
+ int w= s->b_width;
+ int h= s->b_height;
+ int res;
+
+ for(y=0; y<h; y++){
+ for(x=0; x<w; x++){
+ if ((res = decode_q_branch(s, 0, x, y)) < 0)
+ return res;
+ }
+ }
+ return 0;
+}
+
+static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
+ AVPacket *avpkt)
+{
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
+ SnowContext *s = avctx->priv_data;
+ RangeCoder * const c= &s->c;
+ int bytes_read;
+ AVFrame *picture = data;
+ int level, orientation, plane_index;
+ int res;
+
+ ff_init_range_decoder(c, buf, buf_size);
+ ff_build_rac_states(c, 0.05*(1LL<<32), 256-8);
+
+ s->current_picture.pict_type= AV_PICTURE_TYPE_I; //FIXME I vs. P
+ if(decode_header(s)<0)
+ return -1;
+ if ((res=ff_snow_common_init_after_header(avctx)) < 0)
+ return res;
+
+ // realloc slice buffer for the case that spatial_decomposition_count changed
+ ff_slice_buffer_destroy(&s->sb);
+ if ((res = ff_slice_buffer_init(&s->sb, s->plane[0].height,
+ (MB_SIZE >> s->block_max_depth) +
+ s->spatial_decomposition_count * 11 + 1,
+ s->plane[0].width,
+ s->spatial_idwt_buffer)) < 0)
+ return res;
+
+ for(plane_index=0; plane_index<3; plane_index++){
+ Plane *p= &s->plane[plane_index];
+ p->fast_mc= p->diag_mc && p->htaps==6 && p->hcoeff[0]==40
+ && p->hcoeff[1]==-10
+ && p->hcoeff[2]==2;
+ }
+
+ ff_snow_alloc_blocks(s);
+
+ if(ff_snow_frame_start(s) < 0)
+ return -1;
+ //keyframe flag duplication mess FIXME
+ if(avctx->debug&FF_DEBUG_PICT_INFO)
+ av_log(avctx, AV_LOG_ERROR, "keyframe:%d qlog:%d\n", s->keyframe, s->qlog);
+
+ if ((res = decode_blocks(s)) < 0)
+ return res;
+
+ for(plane_index=0; plane_index<3; plane_index++){
+ Plane *p= &s->plane[plane_index];
+ int w= p->width;
+ int h= p->height;
+ int x, y;
+ int decode_state[MAX_DECOMPOSITIONS][4][1]; /* Stored state info for unpack_coeffs. 1 variable per instance. */
+
+ if(s->avctx->debug&2048){
+ memset(s->spatial_dwt_buffer, 0, sizeof(DWTELEM)*w*h);
+ predict_plane(s, s->spatial_idwt_buffer, plane_index, 1);
+
+ for(y=0; y<h; y++){
+ for(x=0; x<w; x++){
+ int v= s->current_picture.data[plane_index][y*s->current_picture.linesize[plane_index] + x];
+ s->mconly_picture.data[plane_index][y*s->mconly_picture.linesize[plane_index] + x]= v;
+ }
+ }
+ }
+
+ {
+ for(level=0; level<s->spatial_decomposition_count; level++){
+ for(orientation=level ? 1 : 0; orientation<4; orientation++){
+ SubBand *b= &p->band[level][orientation];
+ unpack_coeffs(s, b, b->parent, orientation);
+ }
+ }
+ }
+
+ {
+ const int mb_h= s->b_height << s->block_max_depth;
+ const int block_size = MB_SIZE >> s->block_max_depth;
+ const int block_h = plane_index ? block_size>>s->chroma_v_shift : block_size;
+ int mb_y;
+ DWTCompose cs[MAX_DECOMPOSITIONS];
+ int yd=0, yq=0;
+ int y;
+ int end_y;
+
+ ff_spatial_idwt_buffered_init(cs, &s->sb, w, h, 1, s->spatial_decomposition_type, s->spatial_decomposition_count);
+ for(mb_y=0; mb_y<=mb_h; mb_y++){
+
+ int slice_starty = block_h*mb_y;
+ int slice_h = block_h*(mb_y+1);
+
+ if (!(s->keyframe || s->avctx->debug&512)){
+ slice_starty = FFMAX(0, slice_starty - (block_h >> 1));
+ slice_h -= (block_h >> 1);
+ }
+
+ for(level=0; level<s->spatial_decomposition_count; level++){
+ for(orientation=level ? 1 : 0; orientation<4; orientation++){
+ SubBand *b= &p->band[level][orientation];
+ int start_y;
+ int end_y;
+ int our_mb_start = mb_y;
+ int our_mb_end = (mb_y + 1);
+ const int extra= 3;
+ start_y = (mb_y ? ((block_h * our_mb_start) >> (s->spatial_decomposition_count - level)) + s->spatial_decomposition_count - level + extra: 0);
+ end_y = (((block_h * our_mb_end) >> (s->spatial_decomposition_count - level)) + s->spatial_decomposition_count - level + extra);
+ if (!(s->keyframe || s->avctx->debug&512)){
+ start_y = FFMAX(0, start_y - (block_h >> (1+s->spatial_decomposition_count - level)));
+ end_y = FFMAX(0, end_y - (block_h >> (1+s->spatial_decomposition_count - level)));
+ }
+ start_y = FFMIN(b->height, start_y);
+ end_y = FFMIN(b->height, end_y);
+
+ if (start_y != end_y){
+ if (orientation == 0){
+ SubBand * correlate_band = &p->band[0][0];
+ int correlate_end_y = FFMIN(b->height, end_y + 1);
+ int correlate_start_y = FFMIN(b->height, (start_y ? start_y + 1 : 0));
+ decode_subband_slice_buffered(s, correlate_band, &s->sb, correlate_start_y, correlate_end_y, decode_state[0][0]);
+ correlate_slice_buffered(s, &s->sb, correlate_band, correlate_band->ibuf, correlate_band->stride, 1, 0, correlate_start_y, correlate_end_y);
+ dequantize_slice_buffered(s, &s->sb, correlate_band, correlate_band->ibuf, correlate_band->stride, start_y, end_y);
+ }
+ else
+ decode_subband_slice_buffered(s, b, &s->sb, start_y, end_y, decode_state[level][orientation]);
+ }
+ }
+ }
+
+ for(; yd<slice_h; yd+=4){
+ ff_spatial_idwt_buffered_slice(&s->dwt, cs, &s->sb, s->temp_idwt_buffer, w, h, 1, s->spatial_decomposition_type, s->spatial_decomposition_count, yd);
+ }
+
+ if(s->qlog == LOSSLESS_QLOG){
+ for(; yq<slice_h && yq<h; yq++){
+ IDWTELEM * line = slice_buffer_get_line(&s->sb, yq);
+ for(x=0; x<w; x++){
+ line[x] <<= FRAC_BITS;
+ }
+ }
+ }
+
+ predict_slice_buffered(s, &s->sb, s->spatial_idwt_buffer, plane_index, 1, mb_y);
+
+ y = FFMIN(p->height, slice_starty);
+ end_y = FFMIN(p->height, slice_h);
+ while(y < end_y)
+ ff_slice_buffer_release(&s->sb, y++);
+ }
+
+ ff_slice_buffer_flush(&s->sb);
+ }
+
+ }
+
+ emms_c();
+
+ ff_snow_release_buffer(avctx);
+
+ if(!(s->avctx->debug&2048))
+ av_frame_ref(picture, &s->current_picture);
+ else
+ av_frame_ref(picture, &s->mconly_picture);
+
+ *got_frame = 1;
+
+ bytes_read= c->bytestream - c->bytestream_start;
+ if(bytes_read ==0) av_log(s->avctx, AV_LOG_ERROR, "error at end of frame\n"); //FIXME
+
+ return bytes_read;
+}
+
+static av_cold int decode_end(AVCodecContext *avctx)
+{
+ SnowContext *s = avctx->priv_data;
+
+ ff_slice_buffer_destroy(&s->sb);
+
+ ff_snow_common_end(s);
+
+ return 0;
+}
+
+AVCodec ff_snow_decoder = {
+ .name = "snow",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_SNOW,
+ .priv_data_size = sizeof(SnowContext),
+ .init = decode_init,
+ .close = decode_end,
+ .decode = decode_frame,
+ .capabilities = CODEC_CAP_DR1 /*| CODEC_CAP_DRAW_HORIZ_BAND*/,
+ .long_name = NULL_IF_CONFIG_SMALL("Snow"),
+};