3 * Copyright (c) 2003 Michael Niedermayer
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
27 #include "libavutil/intreadwrite.h"
31 #include "bytestream.h"
36 #define BLOCK_TYPE_VLC_BITS 5
37 #define ACDC_VLC_BITS 9
39 #define CFRAME_BUFFER_COUNT 100
41 static const uint8_t block_type_tab[2][4][8][2]={
44 { 0,1}, { 2,2}, { 6,3}, {14,4}, {30,5}, {31,5}, { 0,0}
46 { 0,1}, { 0,0}, { 2,2}, { 6,3}, {14,4}, {15,4}, { 0,0}
48 { 0,1}, { 2,2}, { 0,0}, { 6,3}, {14,4}, {15,4}, { 0,0}
50 { 0,1}, { 0,0}, { 0,0}, { 2,2}, { 6,3}, {14,4}, {15,4}
54 { 1,2}, { 4,3}, { 5,3}, {0,2}, {6,3}, {7,3}, {0,0}
56 { 1,2}, { 0,0}, { 2,2}, {0,2}, {6,3}, {7,3}, {0,0}
58 { 1,2}, { 2,2}, { 0,0}, {0,2}, {6,3}, {7,3}, {0,0}
60 { 1,2}, { 0,0}, { 0,0}, {0,2}, {2,2}, {6,3}, {7,3}
65 static const uint8_t size2index[4][4]={
72 static const int8_t mv[256][2]={
73 { 0, 0},{ 0, -1},{ -1, 0},{ 1, 0},{ 0, 1},{ -1, -1},{ 1, -1},{ -1, 1},
74 { 1, 1},{ 0, -2},{ -2, 0},{ 2, 0},{ 0, 2},{ -1, -2},{ 1, -2},{ -2, -1},
75 { 2, -1},{ -2, 1},{ 2, 1},{ -1, 2},{ 1, 2},{ -2, -2},{ 2, -2},{ -2, 2},
76 { 2, 2},{ 0, -3},{ -3, 0},{ 3, 0},{ 0, 3},{ -1, -3},{ 1, -3},{ -3, -1},
77 { 3, -1},{ -3, 1},{ 3, 1},{ -1, 3},{ 1, 3},{ -2, -3},{ 2, -3},{ -3, -2},
78 { 3, -2},{ -3, 2},{ 3, 2},{ -2, 3},{ 2, 3},{ 0, -4},{ -4, 0},{ 4, 0},
79 { 0, 4},{ -1, -4},{ 1, -4},{ -4, -1},{ 4, -1},{ 4, 1},{ -1, 4},{ 1, 4},
80 { -3, -3},{ -3, 3},{ 3, 3},{ -2, -4},{ -4, -2},{ 4, -2},{ -4, 2},{ -2, 4},
81 { 2, 4},{ -3, -4},{ 3, -4},{ 4, -3},{ -5, 0},{ -4, 3},{ -3, 4},{ 3, 4},
82 { -1, -5},{ -5, -1},{ -5, 1},{ -1, 5},{ -2, -5},{ 2, -5},{ 5, -2},{ 5, 2},
83 { -4, -4},{ -4, 4},{ -3, -5},{ -5, -3},{ -5, 3},{ 3, 5},{ -6, 0},{ 0, 6},
84 { -6, -1},{ -6, 1},{ 1, 6},{ 2, -6},{ -6, 2},{ 2, 6},{ -5, -4},{ 5, 4},
85 { 4, 5},{ -6, -3},{ 6, 3},{ -7, 0},{ -1, -7},{ 5, -5},{ -7, 1},{ -1, 7},
86 { 4, -6},{ 6, 4},{ -2, -7},{ -7, 2},{ -3, -7},{ 7, -3},{ 3, 7},{ 6, -5},
87 { 0, -8},{ -1, -8},{ -7, -4},{ -8, 1},{ 4, 7},{ 2, -8},{ -2, 8},{ 6, 6},
88 { -8, 3},{ 5, -7},{ -5, 7},{ 8, -4},{ 0, -9},{ -9, -1},{ 1, 9},{ 7, -6},
89 { -7, 6},{ -5, -8},{ -5, 8},{ -9, 3},{ 9, -4},{ 7, -7},{ 8, -6},{ 6, 8},
90 { 10, 1},{-10, 2},{ 9, -5},{ 10, -3},{ -8, -7},{-10, -4},{ 6, -9},{-11, 0},
91 { 11, 1},{-11, -2},{ -2, 11},{ 7, -9},{ -7, 9},{ 10, 6},{ -4, 11},{ 8, -9},
92 { 8, 9},{ 5, 11},{ 7,-10},{ 12, -3},{ 11, 6},{ -9, -9},{ 8, 10},{ 5, 12},
93 {-11, 7},{ 13, 2},{ 6,-12},{ 10, 9},{-11, 8},{ -7, 12},{ 0, 14},{ 14, -2},
94 { -9, 11},{ -6, 13},{-14, -4},{ -5,-14},{ 5, 14},{-15, -1},{-14, -6},{ 3,-15},
95 { 11,-11},{ -7, 14},{ -5, 15},{ 8,-14},{ 15, 6},{ 3, 16},{ 7,-15},{-16, 5},
96 { 0, 17},{-16, -6},{-10, 14},{-16, 7},{ 12, 13},{-16, 8},{-17, 6},{-18, 3},
97 { -7, 17},{ 15, 11},{ 16, 10},{ 2,-19},{ 3,-19},{-11,-16},{-18, 8},{-19, -6},
98 { 2,-20},{-17,-11},{-10,-18},{ 8, 19},{-21, -1},{-20, 7},{ -4, 21},{ 21, 5},
99 { 15, 16},{ 2,-22},{-10,-20},{-22, 5},{ 20,-11},{ -7,-22},{-12, 20},{ 23, -5},
100 { 13,-20},{ 24, -2},{-15, 19},{-11, 22},{ 16, 19},{ 23,-10},{-18,-18},{ -9,-24},
101 { 24,-10},{ -3, 26},{-23, 13},{-18,-20},{ 17, 21},{ -4, 27},{ 27, 6},{ 1,-28},
102 {-11, 26},{-17,-23},{ 7, 28},{ 11,-27},{ 29, 5},{-23,-19},{-28,-11},{-21, 22},
103 {-30, 7},{-17, 26},{-27, 16},{ 13, 29},{ 19,-26},{ 10,-31},{-14,-30},{ 20,-27},
104 {-29, 18},{-16,-31},{-28,-22},{ 21,-30},{-25, 28},{ 26,-29},{ 25,-32},{-32,-32}
107 // this is simply the scaled down elementwise product of the standard jpeg quantizer table and the AAN premul table
108 static const uint8_t dequant_table[64]={
109 16, 15, 13, 19, 24, 31, 28, 17,
110 17, 23, 25, 31, 36, 63, 45, 21,
111 18, 24, 27, 37, 52, 59, 49, 20,
112 16, 28, 34, 40, 60, 80, 51, 20,
113 18, 31, 48, 66, 68, 86, 56, 21,
114 19, 38, 56, 59, 64, 64, 48, 20,
115 27, 48, 55, 55, 56, 51, 35, 15,
116 20, 35, 34, 32, 31, 22, 15, 8,
119 static VLC block_type_vlc[2][4];
122 typedef struct CFrameBuffer{
123 unsigned int allocated_size;
129 typedef struct FourXContext{
130 AVCodecContext *avctx;
132 AVFrame current_picture, last_picture;
133 GetBitContext pre_gb; ///< ac/dc prefix
140 DECLARE_ALIGNED(16, DCTELEM, block)[6][64];
141 void *bitstream_buffer;
142 unsigned int bitstream_buffer_size;
144 CFrameBuffer cfrm[CFRAME_BUFFER_COUNT];
148 #define FIX_1_082392200 70936
149 #define FIX_1_414213562 92682
150 #define FIX_1_847759065 121095
151 #define FIX_2_613125930 171254
153 #define MULTIPLY(var,const) (((var)*(const)) >> 16)
155 static void idct(DCTELEM block[64]){
156 int tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
157 int tmp10, tmp11, tmp12, tmp13;
158 int z5, z10, z11, z12, z13;
163 tmp10 = block[8*0 + i] + block[8*4 + i];
164 tmp11 = block[8*0 + i] - block[8*4 + i];
166 tmp13 = block[8*2 + i] + block[8*6 + i];
167 tmp12 = MULTIPLY(block[8*2 + i] - block[8*6 + i], FIX_1_414213562) - tmp13;
169 tmp0 = tmp10 + tmp13;
170 tmp3 = tmp10 - tmp13;
171 tmp1 = tmp11 + tmp12;
172 tmp2 = tmp11 - tmp12;
174 z13 = block[8*5 + i] + block[8*3 + i];
175 z10 = block[8*5 + i] - block[8*3 + i];
176 z11 = block[8*1 + i] + block[8*7 + i];
177 z12 = block[8*1 + i] - block[8*7 + i];
180 tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562);
182 z5 = MULTIPLY(z10 + z12, FIX_1_847759065);
183 tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5;
184 tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5;
190 temp[8*0 + i] = tmp0 + tmp7;
191 temp[8*7 + i] = tmp0 - tmp7;
192 temp[8*1 + i] = tmp1 + tmp6;
193 temp[8*6 + i] = tmp1 - tmp6;
194 temp[8*2 + i] = tmp2 + tmp5;
195 temp[8*5 + i] = tmp2 - tmp5;
196 temp[8*4 + i] = tmp3 + tmp4;
197 temp[8*3 + i] = tmp3 - tmp4;
200 for(i=0; i<8*8; i+=8){
201 tmp10 = temp[0 + i] + temp[4 + i];
202 tmp11 = temp[0 + i] - temp[4 + i];
204 tmp13 = temp[2 + i] + temp[6 + i];
205 tmp12 = MULTIPLY(temp[2 + i] - temp[6 + i], FIX_1_414213562) - tmp13;
207 tmp0 = tmp10 + tmp13;
208 tmp3 = tmp10 - tmp13;
209 tmp1 = tmp11 + tmp12;
210 tmp2 = tmp11 - tmp12;
212 z13 = temp[5 + i] + temp[3 + i];
213 z10 = temp[5 + i] - temp[3 + i];
214 z11 = temp[1 + i] + temp[7 + i];
215 z12 = temp[1 + i] - temp[7 + i];
218 tmp11 = MULTIPLY(z11 - z13, FIX_1_414213562);
220 z5 = MULTIPLY(z10 + z12, FIX_1_847759065);
221 tmp10 = MULTIPLY(z12, FIX_1_082392200) - z5;
222 tmp12 = MULTIPLY(z10, - FIX_2_613125930) + z5;
228 block[0 + i] = (tmp0 + tmp7)>>6;
229 block[7 + i] = (tmp0 - tmp7)>>6;
230 block[1 + i] = (tmp1 + tmp6)>>6;
231 block[6 + i] = (tmp1 - tmp6)>>6;
232 block[2 + i] = (tmp2 + tmp5)>>6;
233 block[5 + i] = (tmp2 - tmp5)>>6;
234 block[4 + i] = (tmp3 + tmp4)>>6;
235 block[3 + i] = (tmp3 - tmp4)>>6;
239 static av_cold void init_vlcs(FourXContext *f){
240 static VLC_TYPE table[8][32][2];
244 block_type_vlc[0][i].table= table[i];
245 block_type_vlc[0][i].table_allocated= 32;
246 init_vlc(&block_type_vlc[0][i], BLOCK_TYPE_VLC_BITS, 7,
247 &block_type_tab[0][i][0][1], 2, 1,
248 &block_type_tab[0][i][0][0], 2, 1, INIT_VLC_USE_NEW_STATIC);
252 static void init_mv(FourXContext *f){
255 for(i=0; i<256; i++){
257 f->mv[i] = mv[i][0] + mv[i][1] *f->current_picture.linesize[0]/2;
259 f->mv[i] = (i&15) - 8 + ((i>>4)-8)*f->current_picture.linesize[0]/2;
264 #define LE_CENTRIC_MUL(dst, src, scale, dc) \
266 unsigned tmpval = AV_RN32(src); \
267 tmpval = (tmpval << 16) | (tmpval >> 16); \
268 tmpval = tmpval * (scale) + (dc); \
269 tmpval = (tmpval << 16) | (tmpval >> 16); \
270 AV_WN32A(dst, tmpval); \
273 #define LE_CENTRIC_MUL(dst, src, scale, dc) \
275 unsigned tmpval = AV_RN32(src) * (scale) + (dc); \
276 AV_WN32A(dst, tmpval); \
280 static inline void mcdc(uint16_t *dst, uint16_t *src, int log2w, int h, int stride, int scale, unsigned dc){
287 dst[0] = scale*src[0] + dc;
288 if(scale) src += stride;
294 LE_CENTRIC_MUL(dst, src, scale, dc);
295 if(scale) src += stride;
301 LE_CENTRIC_MUL(dst, src, scale, dc);
302 LE_CENTRIC_MUL(dst + 2, src + 2, scale, dc);
303 if(scale) src += stride;
309 LE_CENTRIC_MUL(dst, src, scale, dc);
310 LE_CENTRIC_MUL(dst + 2, src + 2, scale, dc);
311 LE_CENTRIC_MUL(dst + 4, src + 4, scale, dc);
312 LE_CENTRIC_MUL(dst + 6, src + 6, scale, dc);
313 if(scale) src += stride;
321 static void decode_p_block(FourXContext *f, uint16_t *dst, uint16_t *src, int log2w, int log2h, int stride){
322 const int index= size2index[log2h][log2w];
323 const int h= 1<<log2h;
324 int code= get_vlc2(&f->gb, block_type_vlc[1-(f->version>1)][index].table, BLOCK_TYPE_VLC_BITS, 1);
325 uint16_t *start= (uint16_t*)f->last_picture.data[0];
326 uint16_t *end= start + stride*(f->avctx->height-h+1) - (1<<log2w);
328 assert(code>=0 && code<=6);
331 src += f->mv[bytestream2_get_byte(&f->g)];
332 if(start > src || src > end){
333 av_log(f->avctx, AV_LOG_ERROR, "mv out of pic\n");
336 mcdc(dst, src, log2w, h, stride, 1, 0);
339 decode_p_block(f, dst , src , log2w, log2h, stride);
340 decode_p_block(f, dst + (stride<<log2h), src + (stride<<log2h), log2w, log2h, stride);
343 decode_p_block(f, dst , src , log2w, log2h, stride);
344 decode_p_block(f, dst + (1<<log2w), src + (1<<log2w), log2w, log2h, stride);
345 }else if(code == 3 && f->version<2){
346 mcdc(dst, src, log2w, h, stride, 1, 0);
348 src += f->mv[bytestream2_get_byte(&f->g)];
349 if(start > src || src > end){
350 av_log(f->avctx, AV_LOG_ERROR, "mv out of pic\n");
353 mcdc(dst, src, log2w, h, stride, 1, bytestream2_get_le16(&f->g2));
355 mcdc(dst, src, log2w, h, stride, 0, bytestream2_get_le16(&f->g2));
358 dst[0] = bytestream2_get_le16(&f->g2);
359 dst[1] = bytestream2_get_le16(&f->g2);
361 dst[0 ] = bytestream2_get_le16(&f->g2);
362 dst[stride] = bytestream2_get_le16(&f->g2);
367 static int decode_p_frame(FourXContext *f, const uint8_t *buf, int length){
369 const int width= f->avctx->width;
370 const int height= f->avctx->height;
371 uint16_t *src= (uint16_t*)f->last_picture.data[0];
372 uint16_t *dst= (uint16_t*)f->current_picture.data[0];
373 const int stride= f->current_picture.linesize[0]>>1;
374 unsigned int bitstream_size, bytestream_size, wordstream_size, extra, bytestream_offset, wordstream_offset;
378 bitstream_size= AV_RL32(buf+8);
379 wordstream_size= AV_RL32(buf+12);
380 bytestream_size= AV_RL32(buf+16);
383 bitstream_size = AV_RL16(buf-4);
384 wordstream_size= AV_RL16(buf-2);
385 bytestream_size= FFMAX(length - bitstream_size - wordstream_size, 0);
388 if(bitstream_size+ bytestream_size+ wordstream_size + extra != length
389 || bitstream_size > (1<<26)
390 || bytestream_size > (1<<26)
391 || wordstream_size > (1<<26)
393 av_log(f->avctx, AV_LOG_ERROR, "lengths %d %d %d %d\n", bitstream_size, bytestream_size, wordstream_size,
394 bitstream_size+ bytestream_size+ wordstream_size - length);
398 av_fast_malloc(&f->bitstream_buffer, &f->bitstream_buffer_size, bitstream_size + FF_INPUT_BUFFER_PADDING_SIZE);
399 if (!f->bitstream_buffer)
400 return AVERROR(ENOMEM);
401 f->dsp.bswap_buf(f->bitstream_buffer, (const uint32_t*)(buf + extra), bitstream_size/4);
402 memset((uint8_t*)f->bitstream_buffer + bitstream_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
403 init_get_bits(&f->gb, f->bitstream_buffer, 8*bitstream_size);
405 wordstream_offset = extra + bitstream_size;
406 bytestream_offset = extra + bitstream_size + wordstream_size;
407 bytestream2_init(&f->g2, buf + wordstream_offset, length - wordstream_offset);
408 bytestream2_init(&f->g, buf + bytestream_offset, length - bytestream_offset);
412 for(y=0; y<height; y+=8){
413 for(x=0; x<width; x+=8){
414 decode_p_block(f, dst + x, src + x, 3, 3, stride);
424 * decode block and dequantize.
425 * Note this is almost identical to MJPEG.
427 static int decode_i_block(FourXContext *f, DCTELEM *block){
428 int code, i, j, level, val;
431 val = get_vlc2(&f->pre_gb, f->pre_vlc.table, ACDC_VLC_BITS, 3);
433 av_log(f->avctx, AV_LOG_ERROR, "error dc run != 0\n");
437 val = get_xbits(&f->gb, val);
439 val = val * dequant_table[0] + f->last_dc;
445 code = get_vlc2(&f->pre_gb, f->pre_vlc.table, ACDC_VLC_BITS, 3);
453 level = get_xbits(&f->gb, code & 0xf);
456 av_log(f->avctx, AV_LOG_ERROR, "run %d oveflow\n", i);
460 j= ff_zigzag_direct[i];
461 block[j] = level * dequant_table[j];
471 static inline void idct_put(FourXContext *f, int x, int y){
472 DCTELEM (*block)[64]= f->block;
473 int stride= f->current_picture.linesize[0]>>1;
475 uint16_t *dst = ((uint16_t*)f->current_picture.data[0]) + y * stride + x;
478 block[i][0] += 0x80*8*8;
482 if(!(f->avctx->flags&CODEC_FLAG_GRAY)){
483 for(i=4; i<6; i++) idct(block[i]);
486 /* Note transform is:
487 y= ( 1b + 4g + 2r)/14
488 cb=( 3b - 2g - 1r)/14
489 cr=(-1b - 4g + 5r)/14
493 DCTELEM *temp= block[(x>>2) + 2*(y>>2)] + 2*(x&3) + 2*8*(y&3); //FIXME optimize
494 int cb= block[4][x + 8*y];
495 int cr= block[5][x + 8*y];
496 int cg= (cb + cr)>>1;
502 dst[0 ]= ((y+cb)>>3) + (((y-cg)&0xFC)<<3) + (((y+cr)&0xF8)<<8);
504 dst[1 ]= ((y+cb)>>3) + (((y-cg)&0xFC)<<3) + (((y+cr)&0xF8)<<8);
506 dst[ stride]= ((y+cb)>>3) + (((y-cg)&0xFC)<<3) + (((y+cr)&0xF8)<<8);
508 dst[1+stride]= ((y+cb)>>3) + (((y-cg)&0xFC)<<3) + (((y+cr)&0xF8)<<8);
511 dst += 2*stride - 2*8;
515 static int decode_i_mb(FourXContext *f){
518 f->dsp.clear_blocks(f->block[0]);
521 if(decode_i_block(f, f->block[i]) < 0)
528 static const uint8_t *read_huffman_tables(FourXContext *f, const uint8_t * const buf){
532 uint8_t len_tab[257];
535 const uint8_t *ptr= buf;
538 memset(frequency, 0, sizeof(frequency));
539 memset(up, -1, sizeof(up));
546 for(i=start; i<=end; i++){
547 frequency[i]= *ptr++;
556 while((ptr - buf)&3) ptr++; // 4byte align
558 for(j=257; j<512; j++){
559 int min_freq[2]= {256*256, 256*256};
560 int smallest[2]= {0, 0};
563 if(frequency[i] == 0) continue;
564 if(frequency[i] < min_freq[1]){
565 if(frequency[i] < min_freq[0]){
566 min_freq[1]= min_freq[0]; smallest[1]= smallest[0];
567 min_freq[0]= frequency[i];smallest[0]= i;
569 min_freq[1]= frequency[i];smallest[1]= i;
573 if(min_freq[1] == 256*256) break;
575 frequency[j]= min_freq[0] + min_freq[1];
576 flag[ smallest[0] ]= 0;
577 flag[ smallest[1] ]= 1;
579 up[ smallest[1] ]= j;
580 frequency[ smallest[0] ]= frequency[ smallest[1] ]= 0;
583 for(j=0; j<257; j++){
588 for(node= j; up[node] != -1; node= up[node]){
589 bits += flag[node]<<len;
591 if(len > 31) av_log(f->avctx, AV_LOG_ERROR, "vlc length overflow\n"); //can this happen at all ?
598 if (init_vlc(&f->pre_vlc, ACDC_VLC_BITS, 257,
606 static int mix(int c0, int c1){
607 int blue = 2*(c0&0x001F) + (c1&0x001F);
608 int green= (2*(c0&0x03E0) + (c1&0x03E0))>>5;
609 int red = 2*(c0>>10) + (c1>>10);
610 return red/3*1024 + green/3*32 + blue/3;
613 static int decode_i2_frame(FourXContext *f, const uint8_t *buf, int length){
615 const int width= f->avctx->width;
616 const int height= f->avctx->height;
617 uint16_t *dst= (uint16_t*)f->current_picture.data[0];
618 const int stride= f->current_picture.linesize[0]>>1;
620 for(y=0; y<height; y+=16){
621 for(x=0; x<width; x+=16){
622 unsigned int color[4], bits;
623 memset(color, 0, sizeof(color));
624 //warning following is purely guessed ...
625 color[0]= bytestream_get_le16(&buf);
626 color[1]= bytestream_get_le16(&buf);
628 if(color[0]&0x8000) av_log(NULL, AV_LOG_ERROR, "unk bit 1\n");
629 if(color[1]&0x8000) av_log(NULL, AV_LOG_ERROR, "unk bit 2\n");
631 color[2]= mix(color[0], color[1]);
632 color[3]= mix(color[1], color[0]);
634 bits= bytestream_get_le32(&buf);
635 for(y2=0; y2<16; y2++){
636 for(x2=0; x2<16; x2++){
637 int index= 2*(x2>>2) + 8*(y2>>2);
638 dst[y2*stride+x2]= color[(bits>>index)&3];
643 dst += 16*stride - width;
649 static int decode_i_frame(FourXContext *f, const uint8_t *buf, int length){
651 const int width= f->avctx->width;
652 const int height= f->avctx->height;
653 uint16_t *dst= (uint16_t*)f->current_picture.data[0];
654 const int stride= f->current_picture.linesize[0]>>1;
655 const unsigned int bitstream_size= AV_RL32(buf);
656 int token_count av_unused;
657 unsigned int prestream_size;
658 const uint8_t *prestream;
660 if (length < bitstream_size + 12) {
661 av_log(f->avctx, AV_LOG_ERROR, "packet size too small\n");
662 return AVERROR_INVALIDDATA;
665 token_count = AV_RL32(buf + bitstream_size + 8);
666 prestream_size = 4 * AV_RL32(buf + bitstream_size + 4);
667 prestream = buf + bitstream_size + 12;
669 if(prestream_size + bitstream_size + 12 != length
670 || bitstream_size > (1<<26)
671 || prestream_size > (1<<26)){
672 av_log(f->avctx, AV_LOG_ERROR, "size mismatch %d %d %d\n", prestream_size, bitstream_size, length);
676 prestream= read_huffman_tables(f, prestream);
678 init_get_bits(&f->gb, buf + 4, 8*bitstream_size);
680 prestream_size= length + buf - prestream;
682 av_fast_malloc(&f->bitstream_buffer, &f->bitstream_buffer_size, prestream_size + FF_INPUT_BUFFER_PADDING_SIZE);
683 if (!f->bitstream_buffer)
684 return AVERROR(ENOMEM);
685 f->dsp.bswap_buf(f->bitstream_buffer, (const uint32_t*)prestream, prestream_size/4);
686 memset((uint8_t*)f->bitstream_buffer + prestream_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
687 init_get_bits(&f->pre_gb, f->bitstream_buffer, 8*prestream_size);
689 f->last_dc= 0*128*8*8;
691 for(y=0; y<height; y+=16){
692 for(x=0; x<width; x+=16){
693 if(decode_i_mb(f) < 0)
701 if(get_vlc2(&f->pre_gb, f->pre_vlc.table, ACDC_VLC_BITS, 3) != 256)
702 av_log(f->avctx, AV_LOG_ERROR, "end mismatch\n");
707 static int decode_frame(AVCodecContext *avctx,
708 void *data, int *data_size,
711 const uint8_t *buf = avpkt->data;
712 int buf_size = avpkt->size;
713 FourXContext * const f = avctx->priv_data;
714 AVFrame *picture = data;
716 int i, frame_4cc, frame_size;
718 frame_4cc= AV_RL32(buf);
719 if(buf_size != AV_RL32(buf+4)+8 || buf_size < 20){
720 av_log(f->avctx, AV_LOG_ERROR, "size mismatch %d %d\n", buf_size, AV_RL32(buf+4));
723 if(frame_4cc == AV_RL32("cfrm")){
725 const int data_size= buf_size - 20;
726 const int id= AV_RL32(buf+12);
727 const int whole_size= AV_RL32(buf+16);
730 for(i=0; i<CFRAME_BUFFER_COUNT; i++){
731 if(f->cfrm[i].id && f->cfrm[i].id < avctx->frame_number)
732 av_log(f->avctx, AV_LOG_ERROR, "lost c frame %d\n", f->cfrm[i].id);
735 for(i=0; i<CFRAME_BUFFER_COUNT; i++){
736 if(f->cfrm[i].id == id) break;
737 if(f->cfrm[i].size == 0 ) free_index= i;
740 if(i>=CFRAME_BUFFER_COUNT){
746 cfrm->data= av_fast_realloc(cfrm->data, &cfrm->allocated_size, cfrm->size + data_size + FF_INPUT_BUFFER_PADDING_SIZE);
747 if(!cfrm->data){ //explicit check needed as memcpy below might not catch a NULL
748 av_log(f->avctx, AV_LOG_ERROR, "realloc falure");
752 memcpy(cfrm->data + cfrm->size, buf+20, data_size);
753 cfrm->size += data_size;
755 if(cfrm->size >= whole_size){
757 frame_size= cfrm->size;
759 if(id != avctx->frame_number){
760 av_log(f->avctx, AV_LOG_ERROR, "cframe id mismatch %d %d\n", id, avctx->frame_number);
763 cfrm->size= cfrm->id= 0;
764 frame_4cc= AV_RL32("pfrm");
769 frame_size= buf_size - 12;
772 temp= f->current_picture;
773 f->current_picture= f->last_picture;
774 f->last_picture= temp;
776 p= &f->current_picture;
777 avctx->coded_frame= p;
779 avctx->flags |= CODEC_FLAG_EMU_EDGE; // alternatively we would have to use our own buffer management
782 avctx->release_buffer(avctx, p);
785 if(avctx->get_buffer(avctx, p) < 0){
786 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
790 if(frame_4cc == AV_RL32("ifr2")){
791 p->pict_type= AV_PICTURE_TYPE_I;
792 if(decode_i2_frame(f, buf-4, frame_size) < 0)
794 }else if(frame_4cc == AV_RL32("ifrm")){
795 p->pict_type= AV_PICTURE_TYPE_I;
796 if(decode_i_frame(f, buf, frame_size) < 0)
798 }else if(frame_4cc == AV_RL32("pfrm") || frame_4cc == AV_RL32("pfr2")){
799 if(!f->last_picture.data[0]){
800 f->last_picture.reference= 1;
801 if(avctx->get_buffer(avctx, &f->last_picture) < 0){
802 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
807 p->pict_type= AV_PICTURE_TYPE_P;
808 if(decode_p_frame(f, buf, frame_size) < 0)
810 }else if(frame_4cc == AV_RL32("snd_")){
811 av_log(avctx, AV_LOG_ERROR, "ignoring snd_ chunk length:%d\n", buf_size);
813 av_log(avctx, AV_LOG_ERROR, "ignoring unknown chunk length:%d\n", buf_size);
816 p->key_frame= p->pict_type == AV_PICTURE_TYPE_I;
819 *data_size = sizeof(AVPicture);
827 static av_cold void common_init(AVCodecContext *avctx){
828 FourXContext * const f = avctx->priv_data;
830 dsputil_init(&f->dsp, avctx);
835 static av_cold int decode_init(AVCodecContext *avctx){
836 FourXContext * const f = avctx->priv_data;
838 if(avctx->extradata_size != 4 || !avctx->extradata) {
839 av_log(avctx, AV_LOG_ERROR, "extradata wrong or missing\n");
843 f->version= AV_RL32(avctx->extradata)>>16;
847 if(f->version>2) avctx->pix_fmt= PIX_FMT_RGB565;
848 else avctx->pix_fmt= PIX_FMT_BGR555;
854 static av_cold int decode_end(AVCodecContext *avctx){
855 FourXContext * const f = avctx->priv_data;
858 av_freep(&f->bitstream_buffer);
859 f->bitstream_buffer_size=0;
860 for(i=0; i<CFRAME_BUFFER_COUNT; i++){
861 av_freep(&f->cfrm[i].data);
862 f->cfrm[i].allocated_size= 0;
864 free_vlc(&f->pre_vlc);
865 if(f->current_picture.data[0])
866 avctx->release_buffer(avctx, &f->current_picture);
867 if(f->last_picture.data[0])
868 avctx->release_buffer(avctx, &f->last_picture);
873 AVCodec ff_fourxm_decoder = {
875 .type = AVMEDIA_TYPE_VIDEO,
877 .priv_data_size = sizeof(FourXContext),
880 .decode = decode_frame,
881 .capabilities = CODEC_CAP_DR1,
882 .long_name = NULL_IF_CONFIG_SMALL("4X Movie"),