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 iLBC_Dec_Inst_t decoder;

45 int enhance;

46 } ILBCDecContext;

48 static const AVOption ilbc_dec_options[] = {

49 { "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 },

50 { NULL }

51 };

53 static const AVClass ilbc_dec_class = {

54 .class_name = "libilbc",

55 .item_name = av_default_item_name,

56 .option = ilbc_dec_options,

57 .version = LIBAVUTIL_VERSION_INT,

58 };

60 static av_cold int ilbc_decode_init(AVCodecContext *avctx)

61 {

62 ILBCDecContext *s = avctx->priv_data;

63 int mode;

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

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

67 return AVERROR(EINVAL);

68 }

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

72 avctx->channels = 1;

73 avctx->channel_layout = AV_CH_LAYOUT_MONO;

74 avctx->sample_rate = 8000;

75 avctx->sample_fmt = AV_SAMPLE_FMT_S16;

77 return 0;

78 }

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

81 int *got_frame_ptr, AVPacket *avpkt)

82 {

83 const uint8_t *buf = avpkt->data;

84 int buf_size = avpkt->size;

85 ILBCDecContext *s = avctx->priv_data;

86 AVFrame *frame = data;

87 int ret;

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

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

91 buf_size, s->decoder.no_of_bytes);

92 return AVERROR_INVALIDDATA;

93 }

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

96 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)

97 return ret;

99 WebRtcIlbcfix_DecodeImpl((WebRtc_Word16*) frame->data[0],

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

101

102 *got_frame_ptr = 1;

103

104 return s->decoder.no_of_bytes;

105 }

106

107 AVCodec ff_libilbc_decoder = {

108 .name = "libilbc",

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

110 .type = AVMEDIA_TYPE_AUDIO,

111 .id = AV_CODEC_ID_ILBC,

112 .priv_data_size = sizeof(ILBCDecContext),

113 .init = ilbc_decode_init,

114 .decode = ilbc_decode_frame,

115 .capabilities = CODEC_CAP_DR1,

116 .priv_class = &ilbc_dec_class,

117 };

118

119 typedef struct ILBCEncContext {

120 const AVClass *class;

121 iLBC_Enc_Inst_t encoder;

122 int mode;

123 } ILBCEncContext;

124

125 static const AVOption ilbc_enc_options[] = {

126 { "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 },

127 { NULL }

128 };

129

130 static const AVClass ilbc_enc_class = {

131 .class_name = "libilbc",

132 .item_name = av_default_item_name,

133 .option = ilbc_enc_options,

134 .version = LIBAVUTIL_VERSION_INT,

135 };

136

137 static av_cold int ilbc_encode_init(AVCodecContext *avctx)

138 {

139 ILBCEncContext *s = avctx->priv_data;

140 int mode;

141

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

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

144 return AVERROR(EINVAL);

145 }

146

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

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

149 return AVERROR(EINVAL);

150 }

151

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

153 s->mode = mode;

154 else

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

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

157

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

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

160

161 return 0;

162 }

163

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

165 const AVFrame *frame, int *got_packet_ptr)

166 {

167 ILBCEncContext *s = avctx->priv_data;

168 int ret;

169

170 if ((ret = ff_alloc_packet2(avctx, avpkt, 50)) < 0)

171 return ret;

172

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

174

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

176 *got_packet_ptr = 1;

177 return 0;

178 }

179

180 static const AVCodecDefault ilbc_encode_defaults[] = {

181 { "b", "0" },

182 { NULL }

183 };

184

185 AVCodec ff_libilbc_encoder = {

186 .name = "libilbc",

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

188 .type = AVMEDIA_TYPE_AUDIO,

189 .id = AV_CODEC_ID_ILBC,

190 .priv_data_size = sizeof(ILBCEncContext),

191 .init = ilbc_encode_init,

192 .encode2 = ilbc_encode_frame,

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

194 AV_SAMPLE_FMT_NONE },

195 .defaults = ilbc_encode_defaults,

196 .priv_class = &ilbc_enc_class,

197 };

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