FFmpeg: libavcodec/rl.c Source File

FFmpeg

libavcodec

rl.c

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1 /*

2 * This file is part of FFmpeg.

3 *

4 * FFmpeg is free software; you can redistribute it and/or

5 * modify it under the terms of the GNU Lesser General Public

6 * License as published by the Free Software Foundation; either

7 * version 2.1 of the License, or (at your option) any later version.

8 *

9 * FFmpeg is distributed in the hope that it will be useful,

10 * but WITHOUT ANY WARRANTY; without even the implied warranty of

11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

12 * Lesser General Public License for more details.

13 *

14 * You should have received a copy of the GNU Lesser General Public

15 * License along with FFmpeg; if not, write to the Free Software

16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

17 */

18

19 #include <stdint.h>

20 #include <string.h>

21

22 #include "libavutil/attributes.h"

23 #include "libavutil/avassert.h"

24

25 #include "rl.h"

26

27 av_cold void ff_rl_init(RLTable *rl,

28 uint8_t static_store[2][2 * MAX_RUN + MAX_LEVEL + 3])

29 {

30 int last, run, level, start, end, i;

31

32 /* compute max_level[], max_run[] and index_run[] */

33 for (last = 0; last < 2; last++) {

34 int8_t *max_level = static_store[last];

35 int8_t *max_run = static_store[last] + MAX_RUN + 1;

36 uint8_t *index_run = static_store[last] + MAX_RUN + 1 + MAX_LEVEL + 1;

37 if (last == 0) {

38 start = 0;

39 end = rl->last;

40 } else {

41 start = rl->last;

42 end = rl->n;

43 }

44

45 memset(index_run, rl->n, MAX_RUN + 1);

46 for (i = start; i < end; i++) {

47 run = rl->table_run[i];

48 level = rl->table_level[i];

49 if (index_run[run] == rl->n)

50 index_run[run] = i;

51 if (level > max_level[run])

52 max_level[run] = level;

53 if (run > max_run[level])

54 max_run[level] = run;

55 }

56 rl->max_level[last] = max_level;

57 rl->max_run[last] = max_run;

58 rl->index_run[last] = index_run;

59 }

60 }

61

62 av_cold void ff_rl_init_vlc(RLTable *rl, unsigned static_size)

63 {

64 int i, q;

65 VLCElem table[1500] = { 0 };

66 VLC vlc = { .table = table, .table_allocated = static_size };

67 av_assert0(static_size <= FF_ARRAY_ELEMS(table));

68 init_vlc(&vlc, 9, rl->n + 1, &rl->table_vlc[0][1], 4, 2, &rl->table_vlc[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);

69

70 for (q = 0; q < 32; q++) {

71 int qmul = q * 2;

72 int qadd = (q - 1) | 1;

73

74 if (!rl->rl_vlc[q])

75 return;

76

77 if (q == 0) {

78 qmul = 1;

79 qadd = 0;

80 }

81 for (i = 0; i < vlc.table_size; i++) {

82 int code = vlc.table[i].sym;

83 int len = vlc.table[i].len;

84 int level, run;

85

86 if (len == 0) { // illegal code

87 run = 66;

88 level = MAX_LEVEL;

89 } else if (len < 0) { // more bits needed

90 run = 0;

91 level = code;

92 } else {

93 if (code == rl->n) { // esc

94 run = 66;

95 level = 0;

96 } else {

97 run = rl->table_run[code] + 1;

98 level = rl->table_level[code] * qmul + qadd;

99 if (code >= rl->last) run += 192;

100 }

101 }

102 rl->rl_vlc[q][i].len = len;

103 rl->rl_vlc[q][i].level = level;

104 rl->rl_vlc[q][i].run = run;

105 }

106 }

107 }

uint8_t level

Definition: svq3.c:206

RLTable::index_run

uint8_t * index_run[2]

encoding only

Definition: rl.h:45

#define MAX_RUN

Definition: rl.h:35

#define init_vlc(vlc, nb_bits, nb_codes, bits, bits_wrap, bits_size, codes, codes_wrap, codes_size, flags)

Definition: vlc.h:43

static const uint16_t table[]

Definition: prosumer.c:206

RL_VLC_ELEM::run

uint8_t run

Definition: vlc.h:40

VLCBaseType len

Definition: vlc.h:28

av_cold void ff_rl_init_vlc(RLTable *rl, unsigned static_size)

Initialize rl_vlc from n, last, table_vlc, table_run and table_level.

Definition: rl.c:62

RLTable.

Definition: rl.h:39

VLCBaseType sym

Definition: vlc.h:28

int n

number of entries of table_vlc minus 1

Definition: rl.h:40

#define FF_ARRAY_ELEMS(a)

Definition: sinewin_tablegen.c:29

#define av_cold

Definition: attributes.h:90

RLTable::max_level

int8_t * max_level[2]

encoding & decoding

Definition: rl.h:46

#define av_assert0(cond)

assert() equivalent, that is always enabled.

Definition: avassert.h:37

av_cold void ff_rl_init(RLTable *rl, uint8_t static_store[2][2 *MAX_RUN+MAX_LEVEL+3])

Initialize index_run, max_level and max_run from n, last, table_vlc, table_run and table_level.

Definition: rl.c:27

uint8_t run

Definition: svq3.c:205

RLTable::table_vlc

const uint16_t(* table_vlc)[2]

Definition: rl.h:42

INIT_VLC_USE_NEW_STATIC

#define INIT_VLC_USE_NEW_STATIC

Definition: vlc.h:100

RL_VLC_ELEM::len

int8_t len

Definition: vlc.h:39

#define MAX_LEVEL

Definition: rl.h:36

RLTable::table_level

const int8_t * table_level

Definition: rl.h:44

Definition: vlc.h:27

i

#define i(width, name, range_min, range_max)

Definition: cbs_h2645.c:269

and forward the test the status of outputs and forward it to the corresponding return FFERROR_NOT_READY If the filters stores internally one or a few frame for some it can consider them to be part of the FIFO and delay acknowledging a status change accordingly Example code

Definition: filter_design.txt:178

RLTable::max_run

int8_t * max_run[2]

encoding & decoding

Definition: rl.h:47

int len

Definition: vorbis_enc_data.h:426

Definition: vlc.h:31

int last

number of values for last = 0

Definition: rl.h:41

VLCElem * table

Definition: vlc.h:33

VLC::table_size

int table_size

Definition: vlc.h:34

RLTable::table_run

const int8_t * table_run

Definition: rl.h:43

RLTable::rl_vlc

RL_VLC_ELEM * rl_vlc[32]

decoding only

Definition: rl.h:48

RL_VLC_ELEM::level

int16_t level

Definition: vlc.h:38

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