Imported Debian version 2.5.2~trusty
[deb_ffmpeg.git] / ffmpeg / libavformat / spdifenc.c
... / ...
CommitLineData
1/*
2 * IEC 61937 muxer
3 * Copyright (c) 2009 Bartlomiej Wolowiec
4 * Copyright (c) 2010 Anssi Hannula
5 * Copyright (c) 2010 Carl Eugen Hoyos
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24/**
25 * @file
26 * IEC-61937 encapsulation of various formats, used by S/PDIF
27 * @author Bartlomiej Wolowiec
28 * @author Anssi Hannula
29 * @author Carl Eugen Hoyos
30 */
31
32/*
33 * Terminology used in specification:
34 * data-burst - IEC61937 frame, contains header and encapsuled frame
35 * burst-preambule - IEC61937 frame header, contains 16-bits words named Pa, Pb, Pc and Pd
36 * burst-payload - encapsuled frame
37 * Pa, Pb - syncword - 0xF872, 0x4E1F
38 * Pc - burst-info, contains data-type (bits 0-6), error flag (bit 7), data-type-dependent info (bits 8-12)
39 * and bitstream number (bits 13-15)
40 * data-type - determines type of encapsuled frames
41 * Pd - length code (number of bits or bytes of encapsuled frame - according to data_type)
42 *
43 * IEC 61937 frames at normal usage start every specific count of bytes,
44 * dependent from data-type (spaces between packets are filled by zeros)
45 */
46
47#include <inttypes.h>
48
49#include "avformat.h"
50#include "avio_internal.h"
51#include "spdif.h"
52#include "libavcodec/ac3.h"
53#include "libavcodec/dca.h"
54#include "libavcodec/aacadtsdec.h"
55#include "libavutil/opt.h"
56
57typedef struct IEC61937Context {
58 const AVClass *av_class;
59 enum IEC61937DataType data_type;///< burst info - reference to type of payload of the data-burst
60 int length_code; ///< length code in bits or bytes, depending on data type
61 int pkt_offset; ///< data burst repetition period in bytes
62 uint8_t *buffer; ///< allocated buffer, used for swap bytes
63 int buffer_size; ///< size of allocated buffer
64
65 uint8_t *out_buf; ///< pointer to the outgoing data before byte-swapping
66 int out_bytes; ///< amount of outgoing bytes
67
68 int use_preamble; ///< preamble enabled (disabled for exactly pre-padded DTS)
69 int extra_bswap; ///< extra bswap for payload (for LE DTS => standard BE DTS)
70
71 uint8_t *hd_buf; ///< allocated buffer to concatenate hd audio frames
72 int hd_buf_size; ///< size of the hd audio buffer
73 int hd_buf_count; ///< number of frames in the hd audio buffer
74 int hd_buf_filled; ///< amount of bytes in the hd audio buffer
75
76 int dtshd_skip; ///< counter used for skipping DTS-HD frames
77
78 /* AVOptions: */
79 int dtshd_rate;
80 int dtshd_fallback;
81#define SPDIF_FLAG_BIGENDIAN 0x01
82 int spdif_flags;
83
84 /// function, which generates codec dependent header information.
85 /// Sets data_type and pkt_offset, and length_code, out_bytes, out_buf if necessary
86 int (*header_info) (AVFormatContext *s, AVPacket *pkt);
87} IEC61937Context;
88
89static const AVOption options[] = {
90{ "spdif_flags", "IEC 61937 encapsulation flags", offsetof(IEC61937Context, spdif_flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "spdif_flags" },
91{ "be", "output in big-endian format (for use as s16be)", 0, AV_OPT_TYPE_CONST, {.i64 = SPDIF_FLAG_BIGENDIAN}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "spdif_flags" },
92{ "dtshd_rate", "mux complete DTS frames in HD mode at the specified IEC958 rate (in Hz, default 0=disabled)", offsetof(IEC61937Context, dtshd_rate), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 768000, AV_OPT_FLAG_ENCODING_PARAM },
93{ "dtshd_fallback_time", "min secs to strip HD for after an overflow (-1: till the end, default 60)", offsetof(IEC61937Context, dtshd_fallback), AV_OPT_TYPE_INT, {.i64 = 60}, -1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
94{ NULL },
95};
96
97static const AVClass spdif_class = {
98 .class_name = "spdif",
99 .item_name = av_default_item_name,
100 .option = options,
101 .version = LIBAVUTIL_VERSION_INT,
102};
103
104static int spdif_header_ac3(AVFormatContext *s, AVPacket *pkt)
105{
106 IEC61937Context *ctx = s->priv_data;
107 int bitstream_mode = pkt->data[5] & 0x7;
108
109 ctx->data_type = IEC61937_AC3 | (bitstream_mode << 8);
110 ctx->pkt_offset = AC3_FRAME_SIZE << 2;
111 return 0;
112}
113
114static int spdif_header_eac3(AVFormatContext *s, AVPacket *pkt)
115{
116 IEC61937Context *ctx = s->priv_data;
117 static const uint8_t eac3_repeat[4] = {6, 3, 2, 1};
118 int repeat = 1;
119
120 if ((pkt->data[4] & 0xc0) != 0xc0) /* fscod */
121 repeat = eac3_repeat[(pkt->data[4] & 0x30) >> 4]; /* numblkscod */
122
123 ctx->hd_buf = av_fast_realloc(ctx->hd_buf, &ctx->hd_buf_size, ctx->hd_buf_filled + pkt->size);
124 if (!ctx->hd_buf)
125 return AVERROR(ENOMEM);
126
127 memcpy(&ctx->hd_buf[ctx->hd_buf_filled], pkt->data, pkt->size);
128
129 ctx->hd_buf_filled += pkt->size;
130 if (++ctx->hd_buf_count < repeat){
131 ctx->pkt_offset = 0;
132 return 0;
133 }
134 ctx->data_type = IEC61937_EAC3;
135 ctx->pkt_offset = 24576;
136 ctx->out_buf = ctx->hd_buf;
137 ctx->out_bytes = ctx->hd_buf_filled;
138 ctx->length_code = ctx->hd_buf_filled;
139
140 ctx->hd_buf_count = 0;
141 ctx->hd_buf_filled = 0;
142 return 0;
143}
144
145/*
146 * DTS type IV (DTS-HD) can be transmitted with various frame repetition
147 * periods; longer repetition periods allow for longer packets and therefore
148 * higher bitrate. Longer repetition periods mean that the constant bitrate of
149 * the outputted IEC 61937 stream is higher.
150 * The repetition period is measured in IEC 60958 frames (4 bytes).
151 */
152static int spdif_dts4_subtype(int period)
153{
154 switch (period) {
155 case 512: return 0x0;
156 case 1024: return 0x1;
157 case 2048: return 0x2;
158 case 4096: return 0x3;
159 case 8192: return 0x4;
160 case 16384: return 0x5;
161 }
162 return -1;
163}
164
165static int spdif_header_dts4(AVFormatContext *s, AVPacket *pkt, int core_size,
166 int sample_rate, int blocks)
167{
168 IEC61937Context *ctx = s->priv_data;
169 static const char dtshd_start_code[10] = { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfe, 0xfe };
170 int pkt_size = pkt->size;
171 int period;
172 int subtype;
173
174 if (!core_size) {
175 av_log(s, AV_LOG_ERROR, "HD mode not supported for this format\n");
176 return AVERROR(EINVAL);
177 }
178
179 if (!sample_rate) {
180 av_log(s, AV_LOG_ERROR, "Unknown DTS sample rate for HD\n");
181 return AVERROR_INVALIDDATA;
182 }
183
184 period = ctx->dtshd_rate * (blocks << 5) / sample_rate;
185 subtype = spdif_dts4_subtype(period);
186
187 if (subtype < 0) {
188 av_log(s, AV_LOG_ERROR, "Specified HD rate of %d Hz would require an "
189 "impossible repetition period of %d for the current DTS stream"
190 " (blocks = %d, sample rate = %d)\n", ctx->dtshd_rate, period,
191 blocks << 5, sample_rate);
192 return AVERROR(EINVAL);
193 }
194
195 /* set pkt_offset and DTS IV subtype according to the requested output
196 * rate */
197 ctx->pkt_offset = period * 4;
198 ctx->data_type = IEC61937_DTSHD | subtype << 8;
199
200 /* If the bitrate is too high for transmitting at the selected
201 * repetition period setting, strip DTS-HD until a good amount
202 * of consecutive non-overflowing HD frames have been observed.
203 * This generally only happens if the caller is cramming a Master
204 * Audio stream into 192kHz IEC 60958 (which may or may not fit). */
205 if (sizeof(dtshd_start_code) + 2 + pkt_size
206 > ctx->pkt_offset - BURST_HEADER_SIZE && core_size) {
207 if (!ctx->dtshd_skip)
208 av_log(s, AV_LOG_WARNING, "DTS-HD bitrate too high, "
209 "temporarily sending core only\n");
210 if (ctx->dtshd_fallback > 0)
211 ctx->dtshd_skip = sample_rate * ctx->dtshd_fallback / (blocks << 5);
212 else
213 /* skip permanently (dtshd_fallback == -1) or just once
214 * (dtshd_fallback == 0) */
215 ctx->dtshd_skip = 1;
216 }
217 if (ctx->dtshd_skip && core_size) {
218 pkt_size = core_size;
219 if (ctx->dtshd_fallback >= 0)
220 --ctx->dtshd_skip;
221 }
222
223 ctx->out_bytes = sizeof(dtshd_start_code) + 2 + pkt_size;
224
225 /* Align so that (length_code & 0xf) == 0x8. This is reportedly needed
226 * with some receivers, but the exact requirement is unconfirmed. */
227 ctx->length_code = FFALIGN(ctx->out_bytes + 0x8, 0x10) - 0x8;
228
229 av_fast_malloc(&ctx->hd_buf, &ctx->hd_buf_size, ctx->out_bytes);
230 if (!ctx->hd_buf)
231 return AVERROR(ENOMEM);
232
233 ctx->out_buf = ctx->hd_buf;
234
235 memcpy(ctx->hd_buf, dtshd_start_code, sizeof(dtshd_start_code));
236 AV_WB16(ctx->hd_buf + sizeof(dtshd_start_code), pkt_size);
237 memcpy(ctx->hd_buf + sizeof(dtshd_start_code) + 2, pkt->data, pkt_size);
238
239 return 0;
240}
241
242static int spdif_header_dts(AVFormatContext *s, AVPacket *pkt)
243{
244 IEC61937Context *ctx = s->priv_data;
245 uint32_t syncword_dts = AV_RB32(pkt->data);
246 int blocks;
247 int sample_rate = 0;
248 int core_size = 0;
249
250 if (pkt->size < 9)
251 return AVERROR_INVALIDDATA;
252
253 switch (syncword_dts) {
254 case DCA_MARKER_RAW_BE:
255 blocks = (AV_RB16(pkt->data + 4) >> 2) & 0x7f;
256 core_size = ((AV_RB24(pkt->data + 5) >> 4) & 0x3fff) + 1;
257 sample_rate = avpriv_dca_sample_rates[(pkt->data[8] >> 2) & 0x0f];
258 break;
259 case DCA_MARKER_RAW_LE:
260 blocks = (AV_RL16(pkt->data + 4) >> 2) & 0x7f;
261 ctx->extra_bswap = 1;
262 break;
263 case DCA_MARKER_14B_BE:
264 blocks =
265 (((pkt->data[5] & 0x07) << 4) | ((pkt->data[6] & 0x3f) >> 2));
266 break;
267 case DCA_MARKER_14B_LE:
268 blocks =
269 (((pkt->data[4] & 0x07) << 4) | ((pkt->data[7] & 0x3f) >> 2));
270 ctx->extra_bswap = 1;
271 break;
272 case DCA_HD_MARKER:
273 /* We only handle HD frames that are paired with core. However,
274 sometimes DTS-HD streams with core have a stray HD frame without
275 core in the beginning of the stream. */
276 av_log(s, AV_LOG_ERROR, "stray DTS-HD frame\n");
277 return AVERROR_INVALIDDATA;
278 default:
279 av_log(s, AV_LOG_ERROR, "bad DTS syncword 0x%"PRIx32"\n", syncword_dts);
280 return AVERROR_INVALIDDATA;
281 }
282 blocks++;
283
284 if (ctx->dtshd_rate)
285 /* DTS type IV output requested */
286 return spdif_header_dts4(s, pkt, core_size, sample_rate, blocks);
287
288 switch (blocks) {
289 case 512 >> 5: ctx->data_type = IEC61937_DTS1; break;
290 case 1024 >> 5: ctx->data_type = IEC61937_DTS2; break;
291 case 2048 >> 5: ctx->data_type = IEC61937_DTS3; break;
292 default:
293 av_log(s, AV_LOG_ERROR, "%i samples in DTS frame not supported\n",
294 blocks << 5);
295 return AVERROR(ENOSYS);
296 }
297
298 /* discard extraneous data by default */
299 if (core_size && core_size < pkt->size) {
300 ctx->out_bytes = core_size;
301 ctx->length_code = core_size << 3;
302 }
303
304 ctx->pkt_offset = blocks << 7;
305
306 if (ctx->out_bytes == ctx->pkt_offset) {
307 /* The DTS stream fits exactly into the output stream, so skip the
308 * preamble as it would not fit in there. This is the case for dts
309 * discs and dts-in-wav. */
310 ctx->use_preamble = 0;
311 } else if (ctx->out_bytes > ctx->pkt_offset - BURST_HEADER_SIZE) {
312 avpriv_request_sample(s, "Unrecognized large DTS frame");
313 /* This will fail with a "bitrate too high" in the caller */
314 }
315
316 return 0;
317}
318
319static const enum IEC61937DataType mpeg_data_type[2][3] = {
320 // LAYER1 LAYER2 LAYER3
321 { IEC61937_MPEG2_LAYER1_LSF, IEC61937_MPEG2_LAYER2_LSF, IEC61937_MPEG2_LAYER3_LSF },//MPEG2 LSF
322 { IEC61937_MPEG1_LAYER1, IEC61937_MPEG1_LAYER23, IEC61937_MPEG1_LAYER23 }, //MPEG1
323};
324
325static int spdif_header_mpeg(AVFormatContext *s, AVPacket *pkt)
326{
327 IEC61937Context *ctx = s->priv_data;
328 int version = (pkt->data[1] >> 3) & 3;
329 int layer = 3 - ((pkt->data[1] >> 1) & 3);
330 int extension = pkt->data[2] & 1;
331
332 if (layer == 3 || version == 1) {
333 av_log(s, AV_LOG_ERROR, "Wrong MPEG file format\n");
334 return AVERROR_INVALIDDATA;
335 }
336 av_log(s, AV_LOG_DEBUG, "version: %i layer: %i extension: %i\n", version, layer, extension);
337 if (version == 2 && extension) {
338 ctx->data_type = IEC61937_MPEG2_EXT;
339 ctx->pkt_offset = 4608;
340 } else {
341 ctx->data_type = mpeg_data_type [version & 1][layer];
342 ctx->pkt_offset = spdif_mpeg_pkt_offset[version & 1][layer];
343 }
344 // TODO Data type dependent info (normal/karaoke, dynamic range control)
345 return 0;
346}
347
348static int spdif_header_aac(AVFormatContext *s, AVPacket *pkt)
349{
350 IEC61937Context *ctx = s->priv_data;
351 AACADTSHeaderInfo hdr;
352 GetBitContext gbc;
353 int ret;
354
355 init_get_bits(&gbc, pkt->data, AAC_ADTS_HEADER_SIZE * 8);
356 ret = avpriv_aac_parse_header(&gbc, &hdr);
357 if (ret < 0) {
358 av_log(s, AV_LOG_ERROR, "Wrong AAC file format\n");
359 return AVERROR_INVALIDDATA;
360 }
361
362 ctx->pkt_offset = hdr.samples << 2;
363 switch (hdr.num_aac_frames) {
364 case 1:
365 ctx->data_type = IEC61937_MPEG2_AAC;
366 break;
367 case 2:
368 ctx->data_type = IEC61937_MPEG2_AAC_LSF_2048;
369 break;
370 case 4:
371 ctx->data_type = IEC61937_MPEG2_AAC_LSF_4096;
372 break;
373 default:
374 av_log(s, AV_LOG_ERROR,
375 "%"PRIu32" samples in AAC frame not supported\n", hdr.samples);
376 return AVERROR(EINVAL);
377 }
378 //TODO Data type dependent info (LC profile/SBR)
379 return 0;
380}
381
382
383/*
384 * It seems Dolby TrueHD frames have to be encapsulated in MAT frames before
385 * they can be encapsulated in IEC 61937.
386 * Here we encapsulate 24 TrueHD frames in a single MAT frame, padding them
387 * to achieve constant rate.
388 * The actual format of a MAT frame is unknown, but the below seems to work.
389 * However, it seems it is not actually necessary for the 24 TrueHD frames to
390 * be in an exact alignment with the MAT frame.
391 */
392#define MAT_FRAME_SIZE 61424
393#define TRUEHD_FRAME_OFFSET 2560
394#define MAT_MIDDLE_CODE_OFFSET -4
395
396static int spdif_header_truehd(AVFormatContext *s, AVPacket *pkt)
397{
398 IEC61937Context *ctx = s->priv_data;
399 int mat_code_length = 0;
400 static const char mat_end_code[16] = { 0xC3, 0xC2, 0xC0, 0xC4, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x97, 0x11 };
401
402 if (!ctx->hd_buf_count) {
403 static const char mat_start_code[20] = { 0x07, 0x9E, 0x00, 0x03, 0x84, 0x01, 0x01, 0x01, 0x80, 0x00, 0x56, 0xA5, 0x3B, 0xF4, 0x81, 0x83, 0x49, 0x80, 0x77, 0xE0 };
404 mat_code_length = sizeof(mat_start_code) + BURST_HEADER_SIZE;
405 memcpy(ctx->hd_buf, mat_start_code, sizeof(mat_start_code));
406
407 } else if (ctx->hd_buf_count == 12) {
408 static const char mat_middle_code[12] = { 0xC3, 0xC1, 0x42, 0x49, 0x3B, 0xFA, 0x82, 0x83, 0x49, 0x80, 0x77, 0xE0 };
409 mat_code_length = sizeof(mat_middle_code) + MAT_MIDDLE_CODE_OFFSET;
410 memcpy(&ctx->hd_buf[12 * TRUEHD_FRAME_OFFSET - BURST_HEADER_SIZE + MAT_MIDDLE_CODE_OFFSET],
411 mat_middle_code, sizeof(mat_middle_code));
412 }
413
414 if (pkt->size > TRUEHD_FRAME_OFFSET - mat_code_length) {
415 /* if such frames exist, we'd need some more complex logic to
416 * distribute the TrueHD frames in the MAT frame */
417 avpriv_request_sample(s, "Too large TrueHD frame of %d bytes",
418 pkt->size);
419 return AVERROR_PATCHWELCOME;
420 }
421
422 memcpy(&ctx->hd_buf[ctx->hd_buf_count * TRUEHD_FRAME_OFFSET - BURST_HEADER_SIZE + mat_code_length],
423 pkt->data, pkt->size);
424 memset(&ctx->hd_buf[ctx->hd_buf_count * TRUEHD_FRAME_OFFSET - BURST_HEADER_SIZE + mat_code_length + pkt->size],
425 0, TRUEHD_FRAME_OFFSET - pkt->size - mat_code_length);
426
427 if (++ctx->hd_buf_count < 24){
428 ctx->pkt_offset = 0;
429 return 0;
430 }
431 memcpy(&ctx->hd_buf[MAT_FRAME_SIZE - sizeof(mat_end_code)], mat_end_code, sizeof(mat_end_code));
432 ctx->hd_buf_count = 0;
433
434 ctx->data_type = IEC61937_TRUEHD;
435 ctx->pkt_offset = 61440;
436 ctx->out_buf = ctx->hd_buf;
437 ctx->out_bytes = MAT_FRAME_SIZE;
438 ctx->length_code = MAT_FRAME_SIZE;
439 return 0;
440}
441
442static int spdif_write_header(AVFormatContext *s)
443{
444 IEC61937Context *ctx = s->priv_data;
445
446 switch (s->streams[0]->codec->codec_id) {
447 case AV_CODEC_ID_AC3:
448 ctx->header_info = spdif_header_ac3;
449 break;
450 case AV_CODEC_ID_EAC3:
451 ctx->header_info = spdif_header_eac3;
452 break;
453 case AV_CODEC_ID_MP1:
454 case AV_CODEC_ID_MP2:
455 case AV_CODEC_ID_MP3:
456 ctx->header_info = spdif_header_mpeg;
457 break;
458 case AV_CODEC_ID_DTS:
459 ctx->header_info = spdif_header_dts;
460 break;
461 case AV_CODEC_ID_AAC:
462 ctx->header_info = spdif_header_aac;
463 break;
464 case AV_CODEC_ID_TRUEHD:
465 ctx->header_info = spdif_header_truehd;
466 ctx->hd_buf = av_malloc(MAT_FRAME_SIZE);
467 if (!ctx->hd_buf)
468 return AVERROR(ENOMEM);
469 break;
470 default:
471 av_log(s, AV_LOG_ERROR, "codec not supported\n");
472 return AVERROR_PATCHWELCOME;
473 }
474 return 0;
475}
476
477static int spdif_write_trailer(AVFormatContext *s)
478{
479 IEC61937Context *ctx = s->priv_data;
480 av_freep(&ctx->buffer);
481 av_freep(&ctx->hd_buf);
482 return 0;
483}
484
485static av_always_inline void spdif_put_16(IEC61937Context *ctx,
486 AVIOContext *pb, unsigned int val)
487{
488 if (ctx->spdif_flags & SPDIF_FLAG_BIGENDIAN)
489 avio_wb16(pb, val);
490 else
491 avio_wl16(pb, val);
492}
493
494static int spdif_write_packet(struct AVFormatContext *s, AVPacket *pkt)
495{
496 IEC61937Context *ctx = s->priv_data;
497 int ret, padding;
498
499 ctx->out_buf = pkt->data;
500 ctx->out_bytes = pkt->size;
501 ctx->length_code = FFALIGN(pkt->size, 2) << 3;
502 ctx->use_preamble = 1;
503 ctx->extra_bswap = 0;
504
505 ret = ctx->header_info(s, pkt);
506 if (ret < 0)
507 return ret;
508 if (!ctx->pkt_offset)
509 return 0;
510
511 padding = (ctx->pkt_offset - ctx->use_preamble * BURST_HEADER_SIZE - ctx->out_bytes) & ~1;
512 if (padding < 0) {
513 av_log(s, AV_LOG_ERROR, "bitrate is too high\n");
514 return AVERROR(EINVAL);
515 }
516
517 if (ctx->use_preamble) {
518 spdif_put_16(ctx, s->pb, SYNCWORD1); //Pa
519 spdif_put_16(ctx, s->pb, SYNCWORD2); //Pb
520 spdif_put_16(ctx, s->pb, ctx->data_type); //Pc
521 spdif_put_16(ctx, s->pb, ctx->length_code);//Pd
522 }
523
524 if (ctx->extra_bswap ^ (ctx->spdif_flags & SPDIF_FLAG_BIGENDIAN)) {
525 avio_write(s->pb, ctx->out_buf, ctx->out_bytes & ~1);
526 } else {
527 av_fast_malloc(&ctx->buffer, &ctx->buffer_size, ctx->out_bytes + FF_INPUT_BUFFER_PADDING_SIZE);
528 if (!ctx->buffer)
529 return AVERROR(ENOMEM);
530 ff_spdif_bswap_buf16((uint16_t *)ctx->buffer, (uint16_t *)ctx->out_buf, ctx->out_bytes >> 1);
531 avio_write(s->pb, ctx->buffer, ctx->out_bytes & ~1);
532 }
533
534 /* a final lone byte has to be MSB aligned */
535 if (ctx->out_bytes & 1)
536 spdif_put_16(ctx, s->pb, ctx->out_buf[ctx->out_bytes - 1] << 8);
537
538 ffio_fill(s->pb, 0, padding);
539
540 av_log(s, AV_LOG_DEBUG, "type=%x len=%i pkt_offset=%i\n",
541 ctx->data_type, ctx->out_bytes, ctx->pkt_offset);
542
543 return 0;
544}
545
546AVOutputFormat ff_spdif_muxer = {
547 .name = "spdif",
548 .long_name = NULL_IF_CONFIG_SMALL("IEC 61937 (used on S/PDIF - IEC958)"),
549 .extensions = "spdif",
550 .priv_data_size = sizeof(IEC61937Context),
551 .audio_codec = AV_CODEC_ID_AC3,
552 .video_codec = AV_CODEC_ID_NONE,
553 .write_header = spdif_write_header,
554 .write_packet = spdif_write_packet,
555 .write_trailer = spdif_write_trailer,
556 .flags = AVFMT_NOTIMESTAMPS,
557 .priv_class = &spdif_class,
558};