📄 ffv1.c
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/* * FFV1 codec for libavcodec * * Copyright (c) 2003 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 *//** * @file ffv1.c * FF Video Codec 1 (an experimental lossless codec) */#include "avcodec.h"#include "bitstream.h"#include "dsputil.h"#include "rangecoder.h"#include "golomb.h"#define MAX_PLANES 4#define CONTEXT_SIZE 32static const int8_t quant3[256]={ 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1, 0,};static const int8_t quant5[256]={ 0, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-1,-1,-1,};static const int8_t quant7[256]={ 0, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-2,-1,-1,};static const int8_t quant9[256]={ 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-3,-2,-2,-2,-2,-1,-1,};static const int8_t quant11[256]={ 0, 1, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-4,-3,-3,-3,-3,-3,-3,-3,-2,-2,-2,-1,};static const int8_t quant13[256]={ 0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-6,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-5,-4,-4,-4,-4,-4,-4,-4,-4,-4,-3,-3,-3,-3,-2,-2,-1,};static const uint8_t log2_run[32]={ 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 9,10,11,12,13,14,15,};typedef struct VlcState{ int16_t drift; uint16_t error_sum; int8_t bias; uint8_t count;} VlcState;typedef struct PlaneContext{ int context_count; uint8_t (*state)[CONTEXT_SIZE]; VlcState *vlc_state; uint8_t interlace_bit_state[2];} PlaneContext;typedef struct FFV1Context{ AVCodecContext *avctx; RangeCoder c; GetBitContext gb; PutBitContext pb; int version; int width, height; int chroma_h_shift, chroma_v_shift; int flags; int picture_number; AVFrame picture; int plane_count; int ac; ///< 1-> CABAC 0-> golomb rice PlaneContext plane[MAX_PLANES]; int16_t quant_table[5][256]; int run_index; int colorspace; DSPContext dsp;}FFV1Context;static av_always_inline int fold(int diff, int bits){ if(bits==8) diff= (int8_t)diff; else{ diff+= 1<<(bits-1); diff&=(1<<bits)-1; diff-= 1<<(bits-1); } return diff;}static inline int predict(int_fast16_t *src, int_fast16_t *last){ const int LT= last[-1]; const int T= last[ 0]; const int L = src[-1]; return mid_pred(L, L + T - LT, T);}static inline int get_context(FFV1Context *f, int_fast16_t *src, int_fast16_t *last, int_fast16_t *last2){ const int LT= last[-1]; const int T= last[ 0]; const int RT= last[ 1]; const int L = src[-1]; if(f->quant_table[3][127]){ const int TT= last2[0]; const int LL= src[-2]; return f->quant_table[0][(L-LT) & 0xFF] + f->quant_table[1][(LT-T) & 0xFF] + f->quant_table[2][(T-RT) & 0xFF] +f->quant_table[3][(LL-L) & 0xFF] + f->quant_table[4][(TT-T) & 0xFF]; }else return f->quant_table[0][(L-LT) & 0xFF] + f->quant_table[1][(LT-T) & 0xFF] + f->quant_table[2][(T-RT) & 0xFF];}static inline void put_symbol(RangeCoder *c, uint8_t *state, int v, int is_signed){ int i; if(v){ const int a= FFABS(v); const int e= av_log2(a); put_rac(c, state+0, 0); assert(e<=9); for(i=0; i<e; i++){ put_rac(c, state+1+i, 1); //1..10 } put_rac(c, state+1+i, 0); for(i=e-1; i>=0; i--){ put_rac(c, state+22+i, (a>>i)&1); //22..31 } if(is_signed) put_rac(c, state+11 + e, v < 0); //11..21 }else{ put_rac(c, state+0, 1); }}static inline int get_symbol(RangeCoder *c, uint8_t *state, int is_signed){ if(get_rac(c, state+0)) return 0; else{ int i, e, a; e= 0; while(get_rac(c, state+1 + e)){ //1..10 e++; } assert(e<=9); a= 1; for(i=e-1; i>=0; i--){ a += a + get_rac(c, state+22 + i); //22..31 } if(is_signed && get_rac(c, state+11 + e)) //11..21 return -a; else return a; }}static inline void update_vlc_state(VlcState * const state, const int v){ int drift= state->drift; int count= state->count; state->error_sum += FFABS(v); drift += v; if(count == 128){ //FIXME variable count >>= 1; drift >>= 1; state->error_sum >>= 1; } count++; if(drift <= -count){ if(state->bias > -128) state->bias--; drift += count; if(drift <= -count) drift= -count + 1; }else if(drift > 0){ if(state->bias < 127) state->bias++; drift -= count; if(drift > 0) drift= 0; } state->drift= drift; state->count= count;}static inline void put_vlc_symbol(PutBitContext *pb, VlcState * const state, int v, int bits){ int i, k, code;//printf("final: %d ", v); v = fold(v - state->bias, bits); i= state->count; k=0; while(i < state->error_sum){ //FIXME optimize k++; i += i; } assert(k<=8);#if 0 // JPEG LS if(k==0 && 2*state->drift <= - state->count) code= v ^ (-1); else code= v;#else code= v ^ ((2*state->drift + state->count)>>31);#endif//printf("v:%d/%d bias:%d error:%d drift:%d count:%d k:%d\n", v, code, state->bias, state->error_sum, state->drift, state->count, k); set_sr_golomb(pb, code, k, 12, bits); update_vlc_state(state, v);}static inline int get_vlc_symbol(GetBitContext *gb, VlcState * const state, int bits){ int k, i, v, ret; i= state->count; k=0; while(i < state->error_sum){ //FIXME optimize k++; i += i; } assert(k<=8); v= get_sr_golomb(gb, k, 12, bits);//printf("v:%d bias:%d error:%d drift:%d count:%d k:%d", v, state->bias, state->error_sum, state->drift, state->count, k);#if 0 // JPEG LS if(k==0 && 2*state->drift <= - state->count) v ^= (-1);#else v ^= ((2*state->drift + state->count)>>31);#endif ret= fold(v + state->bias, bits); update_vlc_state(state, v);//printf("final: %d\n", ret); return ret;}#ifdef CONFIG_ENCODERSstatic inline int encode_line(FFV1Context *s, int w, int_fast16_t *sample[2], int plane_index, int bits){ PlaneContext * const p= &s->plane[plane_index]; RangeCoder * const c= &s->c; int x; int run_index= s->run_index; int run_count=0; int run_mode=0; if(s->ac){ if(c->bytestream_end - c->bytestream < w*20){ av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n"); return -1; } }else{ if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < w*4){ av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n"); return -1; } } for(x=0; x<w; x++){ int diff, context; context= get_context(s, sample[0]+x, sample[1]+x, sample[2]+x); diff= sample[0][x] - predict(sample[0]+x, sample[1]+x); if(context < 0){ context = -context; diff= -diff; } diff= fold(diff, bits); if(s->ac){ put_symbol(c, p->state[context], diff, 1); }else{ if(context == 0) run_mode=1; if(run_mode){ if(diff){ while(run_count >= 1<<log2_run[run_index]){ run_count -= 1<<log2_run[run_index]; run_index++; put_bits(&s->pb, 1, 1); } put_bits(&s->pb, 1 + log2_run[run_index], run_count); if(run_index) run_index--; run_count=0; run_mode=0; if(diff>0) diff--; }else{ run_count++; } }// printf("count:%d index:%d, mode:%d, x:%d y:%d pos:%d\n", run_count, run_index, run_mode, x, y, (int)put_bits_count(&s->pb)); if(run_mode == 0) put_vlc_symbol(&s->pb, &p->vlc_state[context], diff, bits); } } if(run_mode){ while(run_count >= 1<<log2_run[run_index]){ run_count -= 1<<log2_run[run_index]; run_index++; put_bits(&s->pb, 1, 1); } if(run_count) put_bits(&s->pb, 1, 1); } s->run_index= run_index; return 0;}static void encode_plane(FFV1Context *s, uint8_t *src, int w, int h, int stride, int plane_index){ int x,y,i; const int ring_size= s->avctx->context_model ? 3 : 2; int_fast16_t sample_buffer[ring_size][w+6], *sample[ring_size]; s->run_index=0; memset(sample_buffer, 0, sizeof(sample_buffer)); for(y=0; y<h; y++){ for(i=0; i<ring_size; i++) sample[i]= sample_buffer[(h+i-y)%ring_size]+3; sample[0][-1]= sample[1][0 ]; sample[1][ w]= sample[1][w-1];//{START_TIMER for(x=0; x<w; x++){ sample[0][x]= src[x + stride*y]; } encode_line(s, w, sample, plane_index, 8);//STOP_TIMER("encode line")} }}static void encode_rgb_frame(FFV1Context *s, uint32_t *src, int w, int h, int stride){ int x, y, p, i; const int ring_size= s->avctx->context_model ? 3 : 2; int_fast16_t sample_buffer[3][ring_size][w+6], *sample[3][ring_size]; s->run_index=0; memset(sample_buffer, 0, sizeof(sample_buffer)); for(y=0; y<h; y++){ for(i=0; i<ring_size; i++) for(p=0; p<3; p++) sample[p][i]= sample_buffer[p][(h+i-y)%ring_size]+3; for(x=0; x<w; x++){ int v= src[x + stride*y]; int b= v&0xFF; int g= (v>>8)&0xFF; int r= (v>>16)&0xFF; b -= g; r -= g; g += (b + r)>>2; b += 0x100; r += 0x100;// assert(g>=0 && b>=0 && r>=0);// assert(g<256 && b<512 && r<512); sample[0][0][x]= g; sample[1][0][x]= b; sample[2][0][x]= r; } for(p=0; p<3; p++){ sample[p][0][-1]= sample[p][1][0 ]; sample[p][1][ w]= sample[p][1][w-1]; encode_line(s, w, sample[p], FFMIN(p, 1), 9); } }}static void write_quant_table(RangeCoder *c, int16_t *quant_table){ int last=0; int i; uint8_t state[CONTEXT_SIZE]; memset(state, 128, sizeof(state)); for(i=1; i<128 ; i++){ if(quant_table[i] != quant_table[i-1]){ put_symbol(c, state, i-last-1, 0); last= i; } } put_symbol(c, state, i-last-1, 0);}static void write_header(FFV1Context *f){ uint8_t state[CONTEXT_SIZE]; int i; RangeCoder * const c= &f->c; memset(state, 128, sizeof(state)); put_symbol(c, state, f->version, 0);
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