3 * Copyright (c) 2009 Bartlomiej Wolowiec
5 * This file is part of FFmpeg.
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.
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.
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
24 * IEC-61937 encapsulation of various formats, used by S/PDIF
25 * @author Bartlomiej Wolowiec
29 * Terminology used in specification:
30 * data-burst - IEC958 frame, contains header and encapsuled frame
31 * burst-preambule - IEC958 frame header, contains 16-bits words named Pa, Pb, Pc and Pd
32 * burst-payload - encapsuled frame
33 * Pa, Pb - syncword - 0xF872, 0x4E1F
34 * Pc - burst-info, contains data-type (bits 0-6), error flag (bit 7), data-type-dependent info (bits 8-12)
35 * and bitstream number (bits 13-15)
36 * data-type - determines type of encapsuled frames
37 * Pd - length code (number of bits or bytes of encapsuled frame - according to data_type)
39 * IEC958 frames at normal usage start every specific count of bytes,
40 * dependent from data-type (spaces between packets are filled by zeros)
44 #include "libavcodec/ac3.h"
45 #include "libavcodec/dca.h"
46 #include "libavcodec/aac_parser.h"
48 #define SYNCWORD1 0xF872
49 #define SYNCWORD2 0x4E1F
50 #define BURST_HEADER_SIZE 0x8
53 IEC958_AC3 = 0x01, ///< AC-3 data
54 IEC958_MPEG1_LAYER1 = 0x04, ///< MPEG-1 layer 1
55 IEC958_MPEG1_LAYER23 = 0x05, ///< MPEG-1 layer 2 or 3 data or MPEG-2 without extension
56 IEC958_MPEG2_EXT = 0x06, ///< MPEG-2 data with extension
57 IEC958_MPEG2_AAC = 0x07, ///< MPEG-2 AAC ADTS
58 IEC958_MPEG2_LAYER1_LSF = 0x08, ///< MPEG-2, layer-1 low sampling frequency
59 IEC958_MPEG2_LAYER2_LSF = 0x09, ///< MPEG-2, layer-2 low sampling frequency
60 IEC958_MPEG2_LAYER3_LSF = 0x0A, ///< MPEG-2, layer-3 low sampling frequency
61 IEC958_DTS1 = 0x0B, ///< DTS type I (512 samples)
62 IEC958_DTS2 = 0x0C, ///< DTS type II (1024 samples)
63 IEC958_DTS3 = 0x0D, ///< DTS type III (2048 samples)
64 IEC958_ATRAC = 0x0E, ///< Atrac data
65 IEC958_ATRAC3 = 0x0F, ///< Atrac 3 data
66 IEC958_ATRACX = 0x10, ///< Atrac 3 plus data
67 IEC958_DTSHD = 0x11, ///< DTS HD data
68 IEC958_WMAPRO = 0x12, ///< WMA 9 Professional data
69 IEC958_MPEG2_AAC_LSF_2048 = 0x13, ///< MPEG-2 AAC ADTS half-rate low sampling frequency
70 IEC958_MPEG2_AAC_LSF_4096 = 0x13 | 0x20, ///< MPEG-2 AAC ADTS quarter-rate low sampling frequency
71 IEC958_EAC3 = 0x15, ///< E-AC-3 data
72 IEC958_TRUEHD = 0x16, ///< TrueHD data
75 typedef struct IEC958Context {
76 enum IEC958DataType data_type; ///< burst info - reference to type of payload of the data-burst
77 int pkt_size; ///< length code in bits
78 int pkt_offset; ///< data burst repetition period in bytes
79 uint8_t *buffer; ///< allocated buffer, used for swap bytes
80 int buffer_size; ///< size of allocated buffer
82 /// function, which generates codec dependent header information.
83 /// Sets data_type and data_offset
84 int (*header_info) (AVFormatContext *s, AVPacket *pkt);
88 static void bswap_buf16(uint16_t *dst, const uint16_t *src, int w)
92 for (i = 0; i + 8 <= w; i += 8) {
93 dst[i + 0] = bswap_16(src[i + 0]);
94 dst[i + 1] = bswap_16(src[i + 1]);
95 dst[i + 2] = bswap_16(src[i + 2]);
96 dst[i + 3] = bswap_16(src[i + 3]);
97 dst[i + 4] = bswap_16(src[i + 4]);
98 dst[i + 5] = bswap_16(src[i + 5]);
99 dst[i + 6] = bswap_16(src[i + 6]);
100 dst[i + 7] = bswap_16(src[i + 7]);
103 dst[i + 0] = bswap_16(src[i + 0]);
106 static int spdif_header_ac3(AVFormatContext *s, AVPacket *pkt)
108 IEC958Context *ctx = s->priv_data;
109 int bitstream_mode = pkt->data[6] & 0x7;
111 ctx->data_type = IEC958_AC3 | (bitstream_mode << 8);
112 ctx->pkt_offset = AC3_FRAME_SIZE << 2;
116 static int spdif_header_dts(AVFormatContext *s, AVPacket *pkt)
118 IEC958Context *ctx = s->priv_data;
119 uint32_t syncword_dts = AV_RB32(pkt->data);
122 switch (syncword_dts) {
123 case DCA_MARKER_RAW_BE:
124 blocks = (AV_RB16(pkt->data + 4) >> 2) & 0x7f;
126 case DCA_MARKER_RAW_LE:
127 blocks = (AV_RL16(pkt->data + 4) >> 2) & 0x7f;
129 case DCA_MARKER_14B_BE:
131 (((pkt->data[5] & 0x07) << 4) | ((pkt->data[6] & 0x3f) >> 2));
133 case DCA_MARKER_14B_LE:
135 (((pkt->data[4] & 0x07) << 4) | ((pkt->data[7] & 0x3f) >> 2));
138 av_log(s, AV_LOG_ERROR, "bad DTS syncword 0x%x\n", syncword_dts);
143 case 512 >> 5: ctx->data_type = IEC958_DTS1; break;
144 case 1024 >> 5: ctx->data_type = IEC958_DTS2; break;
145 case 2048 >> 5: ctx->data_type = IEC958_DTS3; break;
147 av_log(s, AV_LOG_ERROR, "%i samples in DTS frame not supported\n",
151 ctx->pkt_offset = blocks << 7;
156 static const enum IEC958DataType mpeg_data_type[2][3] = {
157 // LAYER1 LAYER2 LAYER3
158 { IEC958_MPEG2_LAYER1_LSF, IEC958_MPEG2_LAYER2_LSF, IEC958_MPEG2_LAYER3_LSF }, //MPEG2 LSF
159 { IEC958_MPEG1_LAYER1, IEC958_MPEG1_LAYER23, IEC958_MPEG1_LAYER23 }, //MPEG1
162 static const uint16_t mpeg_pkt_offset[2][3] = {
163 //LAYER1 LAYER2 LAYER3
164 { 3072, 9216, 4608 }, // MPEG2 LSF
165 { 1536, 4608, 4608 }, // MPEG1
168 static int spdif_header_mpeg(AVFormatContext *s, AVPacket *pkt)
170 IEC958Context *ctx = s->priv_data;
171 int version = (pkt->data[1] >> 3) & 3;
172 int layer = 3 - ((pkt->data[1] >> 1) & 3);
173 int extension = pkt->data[2] & 1;
175 if (layer == 3 || version == 1) {
176 av_log(s, AV_LOG_ERROR, "Wrong MPEG file format\n");
179 av_log(s, AV_LOG_DEBUG, "version: %i layer: %i extension: %i\n", version, layer, extension);
180 if (version == 2 && extension) {
181 ctx->data_type = IEC958_MPEG2_EXT;
182 ctx->pkt_offset = 4608;
184 ctx->data_type = mpeg_data_type [version & 1][layer];
185 ctx->pkt_offset = mpeg_pkt_offset[version & 1][layer];
187 // TODO Data type dependant info (normal/karaoke, dynamic range control)
191 static int spdif_header_aac(AVFormatContext *s, AVPacket *pkt)
193 IEC958Context *ctx = s->priv_data;
194 AACADTSHeaderInfo hdr;
198 init_get_bits(&gbc, pkt->data, AAC_ADTS_HEADER_SIZE * 8);
199 ret = ff_aac_parse_header(&gbc, &hdr);
201 av_log(s, AV_LOG_ERROR, "Wrong AAC file format\n");
205 ctx->pkt_offset = hdr.samples << 2;
206 switch (hdr.num_aac_frames) {
208 ctx->data_type = IEC958_MPEG2_AAC;
211 ctx->data_type = IEC958_MPEG2_AAC_LSF_2048;
214 ctx->data_type = IEC958_MPEG2_AAC_LSF_4096;
217 av_log(s, AV_LOG_ERROR, "%i samples in AAC frame not supported\n",
221 //TODO Data type dependent info (LC profile/SBR)
225 static int spdif_write_header(AVFormatContext *s)
227 IEC958Context *ctx = s->priv_data;
229 switch (s->streams[0]->codec->codec_id) {
231 ctx->header_info = spdif_header_ac3;
236 ctx->header_info = spdif_header_mpeg;
239 ctx->header_info = spdif_header_dts;
242 ctx->header_info = spdif_header_aac;
245 av_log(s, AV_LOG_ERROR, "codec not supported\n");
251 static int spdif_write_trailer(AVFormatContext *s)
253 IEC958Context *ctx = s->priv_data;
254 av_freep(&ctx->buffer);
258 static int spdif_write_packet(struct AVFormatContext *s, AVPacket *pkt)
260 IEC958Context *ctx = s->priv_data;
263 ctx->pkt_size = FFALIGN(pkt->size, 2) << 3;
264 ret = ctx->header_info(s, pkt);
268 padding = (ctx->pkt_offset - BURST_HEADER_SIZE - pkt->size) >> 1;
270 av_log(s, AV_LOG_ERROR, "bitrate is too high\n");
274 put_le16(s->pb, SYNCWORD1); //Pa
275 put_le16(s->pb, SYNCWORD2); //Pb
276 put_le16(s->pb, ctx->data_type); //Pc
277 put_le16(s->pb, ctx->pkt_size); //Pd
280 put_buffer(s->pb, pkt->data, pkt->size & ~1);
282 av_fast_malloc(&ctx->buffer, &ctx->buffer_size, pkt->size + FF_INPUT_BUFFER_PADDING_SIZE);
284 return AVERROR(ENOMEM);
285 bswap_buf16((uint16_t *)ctx->buffer, (uint16_t *)pkt->data, pkt->size >> 1);
286 put_buffer(s->pb, ctx->buffer, pkt->size & ~1);
290 put_be16(s->pb, pkt->data[pkt->size - 1]);
292 for (; padding > 0; padding--)
295 av_log(s, AV_LOG_DEBUG, "type=%x len=%i pkt_offset=%i\n",
296 ctx->data_type, pkt->size, ctx->pkt_offset);
298 put_flush_packet(s->pb);
302 AVOutputFormat spdif_muxer = {
304 NULL_IF_CONFIG_SMALL("IEC958 - S/PDIF (IEC-61937)"),
307 sizeof(IEC958Context),