FFmpeg: libavformat/chromaprint.c Source File

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libavformat

chromaprint.c

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1 /*

2 * Chromaprint fingerprinting muxer

4 *

5 * This file is part of FFmpeg.

6 *

7 * FFmpeg 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.

11 *

12 * FFmpeg 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.

16 *

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

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

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

20 */

22 #include "avformat.h"

23 #include "internal.h"

24 #include "mux.h"

25 #include "libavutil/opt.h"

26 #include <chromaprint.h>

28 #define CPR_VERSION_INT AV_VERSION_INT(CHROMAPRINT_VERSION_MAJOR, \

29 CHROMAPRINT_VERSION_MINOR, \

30 CHROMAPRINT_VERSION_PATCH)

32 typedef enum FingerprintFormat {

33 FINGERPRINT_RAW,

34 FINGERPRINT_COMPRESSED,

35 FINGERPRINT_BASE64,

36 } FingerprintFormat;

38 typedef struct ChromaprintMuxContext {

39 const AVClass *class;

40 int silence_threshold;

41 int algorithm;

42 FingerprintFormat fp_format;

43 #if CPR_VERSION_INT >= AV_VERSION_INT(1, 4, 0)

44 ChromaprintContext *ctx;

45 #else

46 ChromaprintContext ctx;

47 #endif

48 } ChromaprintMuxContext;

50 static void deinit(AVFormatContext *s)

51 {

52 ChromaprintMuxContext *const cpr = s->priv_data;

54 if (cpr->ctx) {

55 ff_lock_avformat();

56 chromaprint_free(cpr->ctx);

57 ff_unlock_avformat();

58 }

59 }

61 static int write_header(AVFormatContext *s)

62 {

63 ChromaprintMuxContext *cpr = s->priv_data;

64 AVStream *st;

66 ff_lock_avformat();

67 cpr->ctx = chromaprint_new(cpr->algorithm);

68 ff_unlock_avformat();

70 if (!cpr->ctx) {

71 av_log(s, AV_LOG_ERROR, "Failed to create chromaprint context.\n");

72 return AVERROR_EXTERNAL;

73 }

75 if (cpr->silence_threshold != -1) {

76 #if CPR_VERSION_INT >= AV_VERSION_INT(0, 7, 0)

77 if (!chromaprint_set_option(cpr->ctx, "silence_threshold", cpr->silence_threshold)) {

78 av_log(s, AV_LOG_ERROR, "Failed to set silence threshold. Setting silence_threshold requires -algorithm 3 option.\n");

79 return AVERROR_EXTERNAL;

80 }

81 #else

82 av_log(s, AV_LOG_ERROR, "Setting the silence threshold requires Chromaprint "

83 "version 0.7.0 or later.\n");

84 return AVERROR(ENOSYS);

85 #endif

86 }

88 if (s->nb_streams != 1) {

89 av_log(s, AV_LOG_ERROR, "Only one stream is supported\n");

90 return AVERROR(EINVAL);

91 }

93 st = s->streams[0];

95 if (st->codecpar->ch_layout.nb_channels > 2) {

96 av_log(s, AV_LOG_ERROR, "Only up to 2 channels are supported\n");

97 return AVERROR(EINVAL);

98 }

100 if (st->codecpar->sample_rate < 1000) {

101 av_log(s, AV_LOG_ERROR, "Sampling rate must be at least 1000\n");

102 return AVERROR(EINVAL);

103 }

104

105 if (!chromaprint_start(cpr->ctx, st->codecpar->sample_rate, st->codecpar->ch_layout.nb_channels)) {

106 av_log(s, AV_LOG_ERROR, "Failed to start chromaprint\n");

107 return AVERROR_EXTERNAL;

108 }

109

110 return 0;

111 }

112

113 static int write_packet(AVFormatContext *s, AVPacket *pkt)

114 {

115 ChromaprintMuxContext *cpr = s->priv_data;

116 return chromaprint_feed(cpr->ctx, (const int16_t *)pkt->data, pkt->size / 2) ? 0 : AVERROR(EINVAL);

117 }

118

119 static int write_trailer(AVFormatContext *s)

120 {

121 ChromaprintMuxContext *cpr = s->priv_data;

122 AVIOContext *pb = s->pb;

123 void *fp = NULL;

124 char *enc_fp = NULL;

125 int size, enc_size, ret = AVERROR_EXTERNAL;

126

127 if (!chromaprint_finish(cpr->ctx)) {

128 av_log(s, AV_LOG_ERROR, "Failed to generate fingerprint\n");

129 goto fail;

130 }

131

132 if (!chromaprint_get_raw_fingerprint(cpr->ctx, (uint32_t **)&fp, &size)) {

133 av_log(s, AV_LOG_ERROR, "Failed to retrieve fingerprint\n");

134 goto fail;

135 }

136

137 switch (cpr->fp_format) {

138 case FINGERPRINT_RAW:

139 avio_write(pb, fp, size * 4); //fp points to array of uint32_t

140 break;

141 case FINGERPRINT_COMPRESSED:

142 case FINGERPRINT_BASE64:

143 if (!chromaprint_encode_fingerprint(fp, size, cpr->algorithm, &enc_fp, &enc_size,

144 cpr->fp_format == FINGERPRINT_BASE64)) {

145 av_log(s, AV_LOG_ERROR, "Failed to encode fingerprint\n");

146 goto fail;

147 }

148 avio_write(pb, enc_fp, enc_size);

149 break;

150 }

151

152 ret = 0;

153 fail:

154 if (fp)

155 chromaprint_dealloc(fp);

156 if (enc_fp)

157 chromaprint_dealloc(enc_fp);

158 return ret;

159 }

160

161 #define OFFSET(x) offsetof(ChromaprintMuxContext, x)

162 #define FLAGS AV_OPT_FLAG_ENCODING_PARAM

163 static const AVOption options[] = {

164 { "silence_threshold", "threshold for detecting silence", OFFSET(silence_threshold), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, 32767, FLAGS },

165 { "algorithm", "version of the fingerprint algorithm", OFFSET(algorithm), AV_OPT_TYPE_INT, { .i64 = CHROMAPRINT_ALGORITHM_DEFAULT }, CHROMAPRINT_ALGORITHM_TEST1, INT_MAX, FLAGS },

166 { "fp_format", "fingerprint format to write", OFFSET(fp_format), AV_OPT_TYPE_INT, { .i64 = FINGERPRINT_BASE64 }, FINGERPRINT_RAW, FINGERPRINT_BASE64, FLAGS, "fp_format" },

167 { "raw", "binary raw fingerprint", 0, AV_OPT_TYPE_CONST, {.i64 = FINGERPRINT_RAW }, INT_MIN, INT_MAX, FLAGS, "fp_format"},

168 { "compressed", "binary compressed fingerprint", 0, AV_OPT_TYPE_CONST, {.i64 = FINGERPRINT_COMPRESSED }, INT_MIN, INT_MAX, FLAGS, "fp_format"},

169 { "base64", "Base64 compressed fingerprint", 0, AV_OPT_TYPE_CONST, {.i64 = FINGERPRINT_BASE64 }, INT_MIN, INT_MAX, FLAGS, "fp_format"},

170 { NULL },

171 };

172

173 static const AVClass chromaprint_class = {

174 .class_name = "chromaprint muxer",

175 .item_name = av_default_item_name,

176 .option = options,

177 .version = LIBAVUTIL_VERSION_INT,

178 };

179

180 const FFOutputFormat ff_chromaprint_muxer = {

181 .p.name = "chromaprint",

182 .p.long_name = NULL_IF_CONFIG_SMALL("Chromaprint"),

183 .priv_data_size = sizeof(ChromaprintMuxContext),

184 .p.audio_codec = AV_NE(AV_CODEC_ID_PCM_S16BE, AV_CODEC_ID_PCM_S16LE),

185 .write_header = write_header,

186 .write_packet = write_packet,

187 .write_trailer = write_trailer,

188 .deinit = deinit,

189 .p.flags = AVFMT_NOTIMESTAMPS,

190 .p.priv_class = &chromaprint_class,

191 };

AV_CODEC_ID_PCM_S16LE

@ AV_CODEC_ID_PCM_S16LE

Definition: codec_id.h:326

ChromaprintMuxContext::algorithm

int algorithm

Definition: chromaprint.c:41

AVOutputFormat::name

const char * name

Definition: avformat.h:508

AVERROR

Filter the word "frame" indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions

opt.h

AVFMT_NOTIMESTAMPS

#define AVFMT_NOTIMESTAMPS

Format does not need / have any timestamps.

Definition: avformat.h:479

write_header

static int write_header(AVFormatContext *s)

Definition: chromaprint.c:61

FingerprintFormat

Definition: chromaprint.c:32

deinit

static void deinit(AVFormatContext *s)