FFmpeg: libavcodec/libilbc.c Source File

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libavcodec

libilbc.c

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1 /*

2 * iLBC decoder/encoder stub

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 <ilbc.h>

24 #include "libavutil/channel_layout.h"

25 #include "libavutil/common.h"

26 #include "libavutil/opt.h"

27 #include "avcodec.h"

28 #include "internal.h"

30 static int get_mode(AVCodecContext *avctx)

31 {

32 if (avctx->block_align == 38)

33 return 20;

34 else if (avctx->block_align == 50)

35 return 30;

36 else if (avctx->bit_rate > 0)

37 return avctx->bit_rate <= 14000 ? 30 : 20;

38 else

39 return -1;

40 }

42 typedef struct ILBCDecContext {

43 const AVClass *class;

44 AVFrame frame;

45 iLBC_Dec_Inst_t decoder;

46 int enhance;

47 } ILBCDecContext;

49 static const AVOption ilbc_dec_options[] = {

50 { "enhance", "Enhance the decoded audio (adds delay)", offsetof(ILBCDecContext, enhance), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_DECODING_PARAM },

51 { NULL }

52 };

54 static const AVClass ilbc_dec_class = {

55 .class_name = "libilbc",

56 .item_name = av_default_item_name,

57 .option = ilbc_dec_options,

58 .version = LIBAVUTIL_VERSION_INT,

59 };

61 static av_cold int ilbc_decode_init(AVCodecContext *avctx)

62 {

63 ILBCDecContext *s = avctx->priv_data;

64 int mode;

66 if ((mode = get_mode(avctx)) < 0) {

67 av_log(avctx, AV_LOG_ERROR, "iLBC frame mode not indicated\n");

68 return AVERROR(EINVAL);

69 }

71 WebRtcIlbcfix_InitDecode(&s->decoder, mode, s->enhance);

72 avcodec_get_frame_defaults(&s->frame);

73 avctx->coded_frame = &s->frame;

75 avctx->channels = 1;

76 avctx->channel_layout = AV_CH_LAYOUT_MONO;

77 avctx->sample_rate = 8000;

78 avctx->sample_fmt = AV_SAMPLE_FMT_S16;

80 return 0;

81 }

83 static int ilbc_decode_frame(AVCodecContext *avctx, void *data,

84 int *got_frame_ptr, AVPacket *avpkt)

85 {

86 const uint8_t *buf = avpkt->data;

87 int buf_size = avpkt->size;

88 ILBCDecContext *s = avctx->priv_data;

89 int ret;

91 if (s->decoder.no_of_bytes > buf_size) {

92 av_log(avctx, AV_LOG_ERROR, "iLBC frame too short (%u, should be %u)\n",

93 buf_size, s->decoder.no_of_bytes);

94 return AVERROR_INVALIDDATA;

95 }

97 s->frame.nb_samples = s->decoder.blockl;

98 if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {

99 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

100 return ret;

101 }

102

103 WebRtcIlbcfix_DecodeImpl((WebRtc_Word16*) s->frame.data[0],

104 (const WebRtc_UWord16*) buf, &s->decoder, 1);

105

106 *got_frame_ptr = 1;

107 *(AVFrame *)data = s->frame;

108

109 return s->decoder.no_of_bytes;

110 }

111

112 AVCodec ff_libilbc_decoder = {

113 .name = "libilbc",

114 .type = AVMEDIA_TYPE_AUDIO,

115 .id = AV_CODEC_ID_ILBC,

116 .priv_data_size = sizeof(ILBCDecContext),

117 .init = ilbc_decode_init,

118 .decode = ilbc_decode_frame,

119 .capabilities = CODEC_CAP_DR1,

120 .long_name = NULL_IF_CONFIG_SMALL("iLBC (Internet Low Bitrate Codec)"),

121 .priv_class = &ilbc_dec_class,

122 };

123

124 typedef struct ILBCEncContext {

125 const AVClass *class;

126 iLBC_Enc_Inst_t encoder;

127 int mode;

128 } ILBCEncContext;

129

130 static const AVOption ilbc_enc_options[] = {

131 { "mode", "iLBC mode (20 or 30 ms frames)", offsetof(ILBCEncContext, mode), AV_OPT_TYPE_INT, { .i64 = 20 }, 20, 30, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM },

132 { NULL }

133 };

134

135 static const AVClass ilbc_enc_class = {

136 .class_name = "libilbc",

137 .item_name = av_default_item_name,

138 .option = ilbc_enc_options,

139 .version = LIBAVUTIL_VERSION_INT,

140 };

141

142 static av_cold int ilbc_encode_init(AVCodecContext *avctx)

143 {

144 ILBCEncContext *s = avctx->priv_data;

145 int mode;

146

147 if (avctx->sample_rate != 8000) {

148 av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");

149 return AVERROR(EINVAL);

150 }

151

152 if (avctx->channels != 1) {

153 av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");

154 return AVERROR(EINVAL);

155 }

156

157 if ((mode = get_mode(avctx)) > 0)

158 s->mode = mode;

159 else

160 s->mode = s->mode != 30 ? 20 : 30;

161 WebRtcIlbcfix_InitEncode(&s->encoder, s->mode);

162

163 avctx->block_align = s->encoder.no_of_bytes;

164 avctx->frame_size = s->encoder.blockl;

165 #if FF_API_OLD_ENCODE_AUDIO

166 avctx->coded_frame = avcodec_alloc_frame();

167 if (!avctx->coded_frame)

168 return AVERROR(ENOMEM);

169 #endif

170

171 return 0;

172 }

173

174 static av_cold int ilbc_encode_close(AVCodecContext *avctx)

175 {

176 #if FF_API_OLD_ENCODE_AUDIO

177 av_freep(&avctx->coded_frame);

178 #endif

179 return 0;

180 }

181

182 static int ilbc_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,

183 const AVFrame *frame, int *got_packet_ptr)

184 {

185 ILBCEncContext *s = avctx->priv_data;

186 int ret;

187

188 if ((ret = ff_alloc_packet(avpkt, 50))) {

189 av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");

190 return ret;

191 }

192

193 WebRtcIlbcfix_EncodeImpl((WebRtc_UWord16*) avpkt->data, (const WebRtc_Word16*) frame->data[0], &s->encoder);

194

195 avpkt->size = s->encoder.no_of_bytes;

196 *got_packet_ptr = 1;

197 return 0;

198 }

199

200 static const AVCodecDefault ilbc_encode_defaults[] = {

201 { "b", "0" },

202 { NULL }

203 };

204

205 AVCodec ff_libilbc_encoder = {

206 .name = "libilbc",

207 .type = AVMEDIA_TYPE_AUDIO,

208 .id = AV_CODEC_ID_ILBC,

209 .priv_data_size = sizeof(ILBCEncContext),

210 .init = ilbc_encode_init,

211 .encode2 = ilbc_encode_frame,

212 .close = ilbc_encode_close,

213 .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,

214 AV_SAMPLE_FMT_NONE },

215 .long_name = NULL_IF_CONFIG_SMALL("iLBC (Internet Low Bitrate Codec)"),

216 .defaults = ilbc_encode_defaults,

217 .priv_class = &ilbc_enc_class,

218 };

Generated on Sat May 25 2013 03:58:35 for FFmpeg by doxygen 1.8.2