Drop Snow codec

Snow is a toy codec with no real-world use and horrible code.

1 files changed, 0 insertions, 576 deletions

diff --git a/libavcodec/snowdec.c b/libavcodec/snowdec.c
deleted file mode 100644
index 603cef0c07..0000000000
--- a/libavcodec/snowdec.c
+++ /dev/null
@@ -1,576 +0,0 @@
-/*
- * Copyright (C) 2004 Michael Niedermayer <michaelni@gmx.at>
- *
- * This file is part of Libav.
- *
- * Libav 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.
- *
- * Libav 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 Libav; 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 "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/2 : block_size;
-    const uint8_t *obmc  = plane_index ? ff_obmc_tab[s->block_max_depth+1] : ff_obmc_tab[s->block_max_depth];
-    int obmc_stride= plane_index ? block_size : 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_w*mb_y; y<FFMIN(h,block_w*(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_w*mb_y; y<FFMIN(h,block_w*(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_w*mb_y - block_w/2,
-                   block_w, block_w,
-                   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);
-        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", 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) <= 0){
-        av_log(s->avctx, AV_LOG_ERROR, "spatial_decomposition_count %d too large for size", s->spatial_decomposition_count);
-        return -1;
-    }
-
-    if (s->chroma_h_shift != 1 || s->chroma_v_shift != 1) {
-        av_log(s->avctx, AV_LOG_ERROR, "Invalid chroma shift\n");
-        return AVERROR_PATCHWELCOME;
-    }
-
-    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", s->block_max_depth);
-        s->block_max_depth= 0;
-        return -1;
-    }
-
-    return 0;
-}
-
-static av_cold int decode_init(AVCodecContext *avctx)
-{
-    int ret;
-
-    avctx->pix_fmt= AV_PIX_FMT_YUV420P;
-
-    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;
-    ff_snow_common_init_after_header(avctx);
-
-    // 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 * 8 + 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_w    = plane_index ? block_size/2 : 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_w*mb_y;
-            int slice_h = block_w*(mb_y+1);
-            if (!(s->keyframe || s->avctx->debug&512)){
-                slice_starty = FFMAX(0, slice_starty - (block_w >> 1));
-                slice_h -= (block_w >> 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_w * our_mb_start) >> (s->spatial_decomposition_count - level)) + s->spatial_decomposition_count - level + extra: 0);
-                    end_y = (((block_w * 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_w >> (1+s->spatial_decomposition_count - level)));
-                        end_y = FFMAX(0, end_y - (block_w >> (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))
-        *picture= s->current_picture;
-    else
-        *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"),
-};