FFmpeg: libavcodec/dolby_e_parse.c Source File

FFmpeg

libavcodec

dolby_e_parse.c

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1 /*

2 * Copyright (C) 2017 foo86

3 *

4 * This file is part of FFmpeg.

5 *

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

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

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

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

10 *

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

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

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

14 * Lesser General Public License for more details.

15 *

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

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

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

19 */

20

21 #include "get_bits.h"

22 #include "put_bits.h"

23 #include "dolby_e.h"

24

25 static const uint8_t nb_programs_tab[MAX_PROG_CONF + 1] = {

26 2, 3, 2, 3, 4, 5, 4, 5, 6, 7, 8, 1, 2, 3, 3, 4, 5, 6, 1, 2, 3, 4, 1, 1

27 };

28

29 static const uint8_t nb_channels_tab[MAX_PROG_CONF + 1] = {

30 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 6, 6, 6, 6, 6, 6, 6, 4, 4, 4, 4, 8, 8

31 };

32

33 static const uint16_t sample_rate_tab[16] = {

34 0, 42965, 43008, 44800, 53706, 53760

35 };

36

37 static int skip_input(DBEContext *s, int nb_words)

38 {

39 if (nb_words > s->input_size) {

40 return AVERROR_INVALIDDATA;

41 }

42

43 s->input += nb_words * s->word_bytes;

44 s->input_size -= nb_words;

45 return 0;

46 }

47

48 static int parse_key(DBEContext *s)

49 {

50 if (s->key_present) {

51 const uint8_t *key = s->input;

52 int ret = skip_input(s, 1);

53 if (ret < 0)

54 return ret;

55 return AV_RB24(key) >> 24 - s->word_bits;

56 }

57 return 0;

58 }

59

60 int ff_dolby_e_convert_input(DBEContext *s, int nb_words, int key)

61 {

62 const uint8_t *src = s->input;

63 uint8_t *dst = s->buffer;

64 PutBitContext pb;

65 int i;

66

67 av_assert0(nb_words <= 1024u);

68

69 if (nb_words > s->input_size) {

70 if (s->avctx)

71 av_log(s->avctx, AV_LOG_ERROR, "Packet too short\n");

72 return AVERROR_INVALIDDATA;

73 }

74

75 switch (s->word_bits) {

76 case 16:

77 for (i = 0; i < nb_words; i++, src += 2, dst += 2)

78 AV_WB16(dst, AV_RB16(src) ^ key);

79 break;

80 case 20:

81 init_put_bits(&pb, s->buffer, sizeof(s->buffer));

82 for (i = 0; i < nb_words; i++, src += 3)

83 put_bits(&pb, 20, AV_RB24(src) >> 4 ^ key);

84 flush_put_bits(&pb);

85 break;

86 case 24:

87 for (i = 0; i < nb_words; i++, src += 3, dst += 3)

88 AV_WB24(dst, AV_RB24(src) ^ key);

89 break;

90 default:

91 av_assert0(0);

92 }

93

94 return init_get_bits(&s->gb, s->buffer, nb_words * s->word_bits);

95 }

96

97 int ff_dolby_e_parse_header(DBEContext *s, const uint8_t *buf, int buf_size)

98 {

99 DolbyEHeaderInfo *const header = &s->metadata;

100 int hdr, ret, key, mtd_size;

101

102 if (buf_size < 3)

103 return AVERROR_INVALIDDATA;

104

105 hdr = AV_RB24(buf);

106 if ((hdr & 0xfffffe) == 0x7888e) {

107 s->word_bits = 24;

108 } else if ((hdr & 0xffffe0) == 0x788e0) {

109 s->word_bits = 20;

110 } else if ((hdr & 0xfffe00) == 0x78e00) {

111 s->word_bits = 16;

112 } else {

113 if (s->avctx)

114 av_log(s->avctx, AV_LOG_ERROR, "Invalid frame header\n");

115 return AVERROR_INVALIDDATA;

116 }

117

118 s->word_bytes = s->word_bits + 7 >> 3;

119 s->input = buf + s->word_bytes;

120 s->input_size = buf_size / s->word_bytes - 1;

121 s->key_present = hdr >> 24 - s->word_bits & 1;

122

123 if ((key = parse_key(s)) < 0)

124 return key;

125 if ((ret = ff_dolby_e_convert_input(s, 1, key)) < 0)

126 return ret;

127

128 skip_bits(&s->gb, 4);

129 mtd_size = get_bits(&s->gb, 10);

130 if (!mtd_size) {

131 if (s->avctx)

132 av_log(s->avctx, AV_LOG_ERROR, "Invalid metadata size\n");

133 return AVERROR_INVALIDDATA;

134 }

135

136 if ((ret = ff_dolby_e_convert_input(s, mtd_size, key)) < 0)

137 return ret;

138

139 skip_bits(&s->gb, 14);

140 header->prog_conf = get_bits(&s->gb, 6);

141 if (header->prog_conf > MAX_PROG_CONF) {

142 if (s->avctx)

143 av_log(s->avctx, AV_LOG_ERROR, "Invalid program configuration\n");

144 return AVERROR_INVALIDDATA;

145 }

146

147 header->nb_channels = nb_channels_tab[header->prog_conf];

148 header->nb_programs = nb_programs_tab[header->prog_conf];

149

150 header->fr_code = get_bits(&s->gb, 4);

151 header->fr_code_orig = get_bits(&s->gb, 4);

152 if (!(header->sample_rate = sample_rate_tab[header->fr_code]) ||

153 !sample_rate_tab[header->fr_code_orig]) {

154 if (s->avctx)

155 av_log(s->avctx, AV_LOG_ERROR, "Invalid frame rate code\n");

156 return AVERROR_INVALIDDATA;

157 }

158

159 skip_bits_long(&s->gb, 88);

160 for (int i = 0; i < header->nb_channels; i++)

161 header->ch_size[i] = get_bits(&s->gb, 10);

162 header->mtd_ext_size = get_bits(&s->gb, 8);

163 header->meter_size = get_bits(&s->gb, 8);

164

165 skip_bits_long(&s->gb, 10 * header->nb_programs);

166 for (int i = 0; i < header->nb_channels; i++) {

167 header->rev_id[i] = get_bits(&s->gb, 4);

168 skip_bits1(&s->gb);

169 header->begin_gain[i] = get_bits(&s->gb, 10);

170 header->end_gain[i] = get_bits(&s->gb, 10);

171 }

172

173 if (get_bits_left(&s->gb) < 0) {

174 if (s->avctx)

175 av_log(s->avctx, AV_LOG_ERROR, "Read past end of metadata\n");

176 return AVERROR_INVALIDDATA;

177 }

178

179 return skip_input(s, mtd_size + 1);

180 }

static void skip_bits_long(GetBitContext *s, int n)

Skips the specified number of bits.

Definition: get_bits.h:278

static int get_bits_left(GetBitContext *gb)

Definition: get_bits.h:695

u

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

Definition: cbs_h2645.c:251

static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)

Initialize the PutBitContext s.

Definition: put_bits.h:62

static void put_bits(Jpeg2000EncoderContext *s, int val, int n)

put n times val bit

Definition: j2kenc.c:223

static int skip_input(DBEContext *s, int nb_words)

Definition: dolby_e_parse.c:37

static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)

Initialize GetBitContext.

Definition: get_bits.h:514

static void skip_bits(GetBitContext *s, int n)

Definition: get_bits.h:381

static unsigned int get_bits(GetBitContext *s, int n)

Read 1-25 bits.

Definition: get_bits.h:335

Definition: dolby_e.h:72

#define AV_LOG_ERROR

Something went wrong and cannot losslessly be recovered.

Definition: log.h:180

s

#define s(width, name)

Definition: cbs_vp9.c:198

#define av_assert0(cond)

assert() equivalent, that is always enabled.

Definition: avassert.h:40

nb_channels_tab

static const uint8_t nb_channels_tab[MAX_PROG_CONF+1]

Definition: dolby_e_parse.c:29

const char * key

Definition: hwcontext_opencl.c:189

Definition: put_bits.h:50

DolbyEHeaderInfo

Definition: dolby_e.h:37

#define AV_WB16(p, v)

Definition: intreadwrite.h:401

ff_dolby_e_parse_header

int ff_dolby_e_parse_header(DBEContext *s, const uint8_t *buf, int buf_size)

Initialize DBEContext and parse Dolby E metadata.

Definition: dolby_e_parse.c:97

uint8_t ptrdiff_t const uint8_t ptrdiff_t int intptr_t intptr_t int int16_t * dst

Definition: dsp.h:83

#define MAX_PROG_CONF

Definition: dolby_e.h:29

#define AV_WB24(p, d)

Definition: intreadwrite.h:446

static const uint8_t header[24]

Definition: sdr2.c:68

static void skip_bits1(GetBitContext *s)

Definition: get_bits.h:413

i

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

Definition: cbs_h2645.c:256

static int parse_key(DBEContext *s)

Definition: dolby_e_parse.c:48

ret

Definition: filter_design.txt:187

static void flush_put_bits(PutBitContext *s)

Pad the end of the output stream with zeros.

Definition: put_bits.h:143

sample_rate_tab

static const uint16_t sample_rate_tab[16]

Definition: dolby_e_parse.c:33

#define av_log(a,...)

Definition: tableprint_vlc.h:27

AVERROR_INVALIDDATA

#define AVERROR_INVALIDDATA

Invalid data found when processing input.

Definition: error.h:61

uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24

Definition: bytestream.h:97

ff_dolby_e_convert_input

int ff_dolby_e_convert_input(DBEContext *s, int nb_words, int key)

Use the provided key to transform the input into data (put into s->buffer) suitable for further proce...

Definition: dolby_e_parse.c:60

#define src

Definition: vp8dsp.c:248

uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16

Definition: bytestream.h:98

nb_programs_tab

static const uint8_t nb_programs_tab[MAX_PROG_CONF+1]

Definition: dolby_e_parse.c:25

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