202 lines
10 KiB
C
202 lines
10 KiB
C
/*
|
|
* H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
|
|
* 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
|
|
* Context Adaptive Binary Arithmetic Coder.
|
|
*/
|
|
|
|
#include <string.h>
|
|
|
|
#include "libavutil/common.h"
|
|
|
|
#include "cabac.h"
|
|
#include "cabac_functions.h"
|
|
|
|
DECLARE_ASM_ALIGNED(1, const uint8_t, ff_h264_cabac_tables)[512 + 4*2*64 + 4*64 + 63] = {
|
|
9,8,7,7,6,6,6,6,5,5,5,5,5,5,5,5,
|
|
4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
|
|
3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
|
|
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,
|
|
2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
|
|
2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
|
|
1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
|
|
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,
|
|
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
|
|
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
|
|
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
|
|
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
|
|
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
|
|
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
|
|
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
|
|
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
|
|
// LPS range
|
|
-128, -128, -128, -128, -128, -128, 123, 123,
|
|
116, 116, 111, 111, 105, 105, 100, 100,
|
|
95, 95, 90, 90, 85, 85, 81, 81,
|
|
77, 77, 73, 73, 69, 69, 66, 66,
|
|
62, 62, 59, 59, 56, 56, 53, 53,
|
|
51, 51, 48, 48, 46, 46, 43, 43,
|
|
41, 41, 39, 39, 37, 37, 35, 35,
|
|
33, 33, 32, 32, 30, 30, 29, 29,
|
|
27, 27, 26, 26, 24, 24, 23, 23,
|
|
22, 22, 21, 21, 20, 20, 19, 19,
|
|
18, 18, 17, 17, 16, 16, 15, 15,
|
|
14, 14, 14, 14, 13, 13, 12, 12,
|
|
12, 12, 11, 11, 11, 11, 10, 10,
|
|
10, 10, 9, 9, 9, 9, 8, 8,
|
|
8, 8, 7, 7, 7, 7, 7, 7,
|
|
6, 6, 6, 6, 6, 6, 2, 2,
|
|
-80, -80, -89, -89, -98, -98, -106, -106,
|
|
-114, -114, -121, -121, -128, -128, 122, 122,
|
|
116, 116, 110, 110, 104, 104, 99, 99,
|
|
94, 94, 89, 89, 85, 85, 80, 80,
|
|
76, 76, 72, 72, 69, 69, 65, 65,
|
|
62, 62, 59, 59, 56, 56, 53, 53,
|
|
50, 50, 48, 48, 45, 45, 43, 43,
|
|
41, 41, 39, 39, 37, 37, 35, 35,
|
|
33, 33, 31, 31, 30, 30, 28, 28,
|
|
27, 27, 26, 26, 24, 24, 23, 23,
|
|
22, 22, 21, 21, 20, 20, 19, 19,
|
|
18, 18, 17, 17, 16, 16, 15, 15,
|
|
14, 14, 14, 14, 13, 13, 12, 12,
|
|
12, 12, 11, 11, 11, 11, 10, 10,
|
|
9, 9, 9, 9, 9, 9, 8, 8,
|
|
8, 8, 7, 7, 7, 7, 2, 2,
|
|
-48, -48, -59, -59, -69, -69, -78, -78,
|
|
-87, -87, -96, -96, -104, -104, -112, -112,
|
|
-119, -119, -126, -126, 123, 123, 117, 117,
|
|
111, 111, 105, 105, 100, 100, 95, 95,
|
|
90, 90, 86, 86, 81, 81, 77, 77,
|
|
73, 73, 69, 69, 66, 66, 63, 63,
|
|
59, 59, 56, 56, 54, 54, 51, 51,
|
|
48, 48, 46, 46, 43, 43, 41, 41,
|
|
39, 39, 37, 37, 35, 35, 33, 33,
|
|
32, 32, 30, 30, 29, 29, 27, 27,
|
|
26, 26, 25, 25, 23, 23, 22, 22,
|
|
21, 21, 20, 20, 19, 19, 18, 18,
|
|
17, 17, 16, 16, 15, 15, 15, 15,
|
|
14, 14, 13, 13, 12, 12, 12, 12,
|
|
11, 11, 11, 11, 10, 10, 10, 10,
|
|
9, 9, 9, 9, 8, 8, 2, 2,
|
|
-16, -16, -29, -29, -40, -40, -51, -51,
|
|
-61, -61, -71, -71, -81, -81, -90, -90,
|
|
-98, -98, -106, -106, -114, -114, -121, -121,
|
|
-128, -128, 122, 122, 116, 116, 110, 110,
|
|
104, 104, 99, 99, 94, 94, 89, 89,
|
|
85, 85, 80, 80, 76, 76, 72, 72,
|
|
69, 69, 65, 65, 62, 62, 59, 59,
|
|
56, 56, 53, 53, 50, 50, 48, 48,
|
|
45, 45, 43, 43, 41, 41, 39, 39,
|
|
37, 37, 35, 35, 33, 33, 31, 31,
|
|
30, 30, 28, 28, 27, 27, 25, 25,
|
|
24, 24, 23, 23, 22, 22, 21, 21,
|
|
20, 20, 19, 19, 18, 18, 17, 17,
|
|
16, 16, 15, 15, 14, 14, 14, 14,
|
|
13, 13, 12, 12, 12, 12, 11, 11,
|
|
11, 11, 10, 10, 9, 9, 2, 2,
|
|
// mlps state
|
|
127, 126, 77, 76, 77, 76, 75, 74,
|
|
75, 74, 75, 74, 73, 72, 73, 72,
|
|
73, 72, 71, 70, 71, 70, 71, 70,
|
|
69, 68, 69, 68, 67, 66, 67, 66,
|
|
67, 66, 65, 64, 65, 64, 63, 62,
|
|
61, 60, 61, 60, 61, 60, 59, 58,
|
|
59, 58, 57, 56, 55, 54, 55, 54,
|
|
53, 52, 53, 52, 51, 50, 49, 48,
|
|
49, 48, 47, 46, 45, 44, 45, 44,
|
|
43, 42, 43, 42, 39, 38, 39, 38,
|
|
37, 36, 37, 36, 33, 32, 33, 32,
|
|
31, 30, 31, 30, 27, 26, 27, 26,
|
|
25, 24, 23, 22, 23, 22, 19, 18,
|
|
19, 18, 17, 16, 15, 14, 13, 12,
|
|
11, 10, 9, 8, 9, 8, 5, 4,
|
|
5, 4, 3, 2, 1, 0, 0, 1,
|
|
2, 3, 4, 5, 6, 7, 8, 9,
|
|
10, 11, 12, 13, 14, 15, 16, 17,
|
|
18, 19, 20, 21, 22, 23, 24, 25,
|
|
26, 27, 28, 29, 30, 31, 32, 33,
|
|
34, 35, 36, 37, 38, 39, 40, 41,
|
|
42, 43, 44, 45, 46, 47, 48, 49,
|
|
50, 51, 52, 53, 54, 55, 56, 57,
|
|
58, 59, 60, 61, 62, 63, 64, 65,
|
|
66, 67, 68, 69, 70, 71, 72, 73,
|
|
74, 75, 76, 77, 78, 79, 80, 81,
|
|
82, 83, 84, 85, 86, 87, 88, 89,
|
|
90, 91, 92, 93, 94, 95, 96, 97,
|
|
98, 99, 100, 101, 102, 103, 104, 105,
|
|
106, 107, 108, 109, 110, 111, 112, 113,
|
|
114, 115, 116, 117, 118, 119, 120, 121,
|
|
122, 123, 124, 125, 124, 125, 126, 127,
|
|
// last_coeff_flag_offset_8x8
|
|
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
|
|
3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4,
|
|
5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8
|
|
};
|
|
|
|
/**
|
|
* @param buf_size size of buf in bits
|
|
*/
|
|
void ff_init_cabac_encoder(CABACContext *c, uint8_t *buf, int buf_size){
|
|
init_put_bits(&c->pb, buf, buf_size);
|
|
|
|
c->low= 0;
|
|
c->range= 0x1FE;
|
|
c->outstanding_count= 0;
|
|
c->pb.bit_left++; //avoids firstBitFlag
|
|
}
|
|
|
|
/**
|
|
*
|
|
* @param buf_size size of buf in bits
|
|
*/
|
|
int ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size){
|
|
c->bytestream_start=
|
|
c->bytestream= buf;
|
|
c->bytestream_end= buf + buf_size;
|
|
|
|
#if CABAC_BITS == 16
|
|
c->low = (*c->bytestream++)<<18;
|
|
c->low+= (*c->bytestream++)<<10;
|
|
// Keep our fetches on a 2-byte boundary as this should avoid ever having to
|
|
// do unaligned loads if the compiler (or asm) optimises the double byte
|
|
// load into a single instruction
|
|
if(((uintptr_t)c->bytestream & 1) == 0) {
|
|
c->low += (1 << 9);
|
|
}
|
|
else {
|
|
c->low += ((*c->bytestream++) << 2) + 2;
|
|
}
|
|
#else
|
|
c->low = (*c->bytestream++)<<10;
|
|
c->low+= ((*c->bytestream++)<<2) + 2;
|
|
#endif
|
|
c->range= 0x1FE;
|
|
if ((c->range<<(CABAC_BITS+1)) < c->low)
|
|
return AVERROR_INVALIDDATA;
|
|
return 0;
|
|
}
|