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1 d4fc91b4 Panagiotis Issaris
/*
2
 * General DV muxer/demuxer
3
 * Copyright (c) 2003 Roman Shaposhnik
4
 *
5
 * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
6
 * of DV technical info.
7
 *
8
 * Raw DV format
9 406792e7 Diego Biurrun
 * Copyright (c) 2002 Fabrice Bellard
10 d4fc91b4 Panagiotis Issaris
 *
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 * 50 Mbps (DVCPRO50) support
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 * Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com>
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
19 b78e7197 Diego Biurrun
 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
24
 * Lesser General Public License for more details.
25
 *
26
 * You should have received a copy of the GNU Lesser General Public
27 b78e7197 Diego Biurrun
 * License along with FFmpeg; if not, write to the Free Software
28 d4fc91b4 Panagiotis Issaris
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29
 */
30
#include <time.h>
31 e950141a Roman Shaposhnik
#include <stdarg.h>
32 e1ae1642 Diego Biurrun
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#include "avformat.h"
34 e1ae1642 Diego Biurrun
#include "internal.h"
35 245976da Diego Biurrun
#include "libavcodec/dvdata.h"
36 d4fc91b4 Panagiotis Issaris
#include "dv.h"
37 245976da Diego Biurrun
#include "libavutil/fifo.h"
38 d4fc91b4 Panagiotis Issaris
39
struct DVMuxContext {
40 75f2c209 Diego Biurrun
    const DVprofile*  sys;           /* current DV profile, e.g.: 525/60, 625/50 */
41
    int               n_ast;         /* number of stereo audio streams (up to 2) */
42
    AVStream         *ast[2];        /* stereo audio streams */
43 41dd680d Michael Niedermayer
    AVFifoBuffer     *audio_data[2]; /* FIFO for storing excessive amounts of PCM */
44 75f2c209 Diego Biurrun
    int               frames;        /* current frame number */
45
    time_t            start_time;    /* recording start time */
46 f94036f1 Diego Biurrun
    int               has_audio;     /* frame under contruction has audio */
47
    int               has_video;     /* frame under contruction has video */
48
    uint8_t           frame_buf[DV_MAX_FRAME_SIZE]; /* frame under contruction */
49 d4fc91b4 Panagiotis Issaris
};
50
51
static const int dv_aaux_packs_dist[12][9] = {
52
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
53
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
54
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
55
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
56
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
57
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
58
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
59
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
60
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
61
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
62
    { 0xff, 0xff, 0xff, 0x50, 0x51, 0x52, 0x53, 0xff, 0xff },
63
    { 0x50, 0x51, 0x52, 0x53, 0xff, 0xff, 0xff, 0xff, 0xff },
64
};
65
66
static int dv_audio_frame_size(const DVprofile* sys, int frame)
67
{
68 f94036f1 Diego Biurrun
    return sys->audio_samples_dist[frame % (sizeof(sys->audio_samples_dist) /
69 d4fc91b4 Panagiotis Issaris
                                            sizeof(sys->audio_samples_dist[0]))];
70
}
71
72 e950141a Roman Shaposhnik
static int dv_write_pack(enum dv_pack_type pack_id, DVMuxContext *c, uint8_t* buf, ...)
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{
74
    struct tm tc;
75
    time_t ct;
76
    int ltc_frame;
77 e950141a Roman Shaposhnik
    va_list ap;
78 d4fc91b4 Panagiotis Issaris
79
    buf[0] = (uint8_t)pack_id;
80
    switch (pack_id) {
81
    case dv_timecode:
82 f94036f1 Diego Biurrun
        ct = (time_t)av_rescale_rnd(c->frames, c->sys->time_base.num,
83
                                    c->sys->time_base.den, AV_ROUND_DOWN);
84 bc60f09b Reimar Döffinger
        brktimegm(ct, &tc);
85
        /*
86
         * LTC drop-frame frame counter drops two frames (0 and 1) every
87
         * minute, unless it is exactly divisible by 10
88
         */
89 f94036f1 Diego Biurrun
        ltc_frame = (c->frames + 2 * ct / 60 - 2 * ct / 600) % c->sys->ltc_divisor;
90 75f2c209 Diego Biurrun
        buf[1] = (0                 << 7) | /* color frame: 0 - unsync; 1 - sync mode */
91
                 (1                 << 6) | /* drop frame timecode: 0 - nondrop; 1 - drop */
92
                 ((ltc_frame / 10)  << 4) | /* tens of frames */
93
                 (ltc_frame % 10);          /* units of frames */
94
        buf[2] = (1                 << 7) | /* biphase mark polarity correction: 0 - even; 1 - odd */
95
                 ((tc.tm_sec / 10)  << 4) | /* tens of seconds */
96
                 (tc.tm_sec % 10);          /* units of seconds */
97
        buf[3] = (1                 << 7) | /* binary group flag BGF0 */
98
                 ((tc.tm_min / 10)  << 4) | /* tens of minutes */
99
                 (tc.tm_min % 10);          /* units of minutes */
100
        buf[4] = (1                 << 7) | /* binary group flag BGF2 */
101
                 (1                 << 6) | /* binary group flag BGF1 */
102
                 ((tc.tm_hour / 10) << 4) | /* tens of hours */
103
                 (tc.tm_hour % 10);         /* units of hours */
104 bc60f09b Reimar Döffinger
        break;
105 d4fc91b4 Panagiotis Issaris
    case dv_audio_source:  /* AAUX source pack */
106 bc60f09b Reimar Döffinger
        va_start(ap, buf);
107
        buf[1] = (1 << 7) | /* locked mode -- SMPTE only supports locked mode */
108
                 (1 << 6) | /* reserved -- always 1 */
109
                 (dv_audio_frame_size(c->sys, c->frames) -
110
                  c->sys->audio_min_samples[0]);
111
                            /* # of samples      */
112
        buf[2] = (0 << 7) | /* multi-stereo      */
113
                 (0 << 5) | /* #of audio channels per block: 0 -- 1 channel */
114
                 (0 << 4) | /* pair bit: 0 -- one pair of channels */
115
                 !!va_arg(ap, int); /* audio mode        */
116
        buf[3] = (1 << 7) | /* res               */
117
                 (1 << 6) | /* multi-language flag */
118
                 (c->sys->dsf << 5) | /*  system: 60fields/50fields */
119
                 (c->sys->n_difchan & 2); /* definition: 0 -- 25Mbps, 2 -- 50Mbps */
120
        buf[4] = (1 << 7) | /* emphasis: 1 -- off */
121
                 (0 << 6) | /* emphasis time constant: 0 -- reserved */
122 910f02a0 Diego Biurrun
                 (0 << 3) | /* frequency: 0 -- 48kHz, 1 -- 44,1kHz, 2 -- 32kHz */
123 bc60f09b Reimar Döffinger
                  0;        /* quantization: 0 -- 16bit linear, 1 -- 12bit nonlinear */
124
        va_end(ap);
125
        break;
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    case dv_audio_control:
127 bc60f09b Reimar Döffinger
        buf[1] = (0 << 6) | /* copy protection: 0 -- unrestricted */
128
                 (1 << 4) | /* input source: 1 -- digital input */
129
                 (3 << 2) | /* compression: 3 -- no information */
130
                  0;        /* misc. info/SMPTE emphasis off */
131
        buf[2] = (1 << 7) | /* recording start point: 1 -- no */
132
                 (1 << 6) | /* recording end point: 1 -- no */
133
                 (1 << 3) | /* recording mode: 1 -- original */
134
                  7;
135
        buf[3] = (1 << 7) | /* direction: 1 -- forward */
136
                 (c->sys->pix_fmt == PIX_FMT_YUV420P ? 0x20 : /* speed */
137 f94036f1 Diego Biurrun
                                                       c->sys->ltc_divisor * 4);
138 bc60f09b Reimar Döffinger
        buf[4] = (1 << 7) | /* reserved -- always 1 */
139
                  0x7f;     /* genre category */
140
        break;
141 d4fc91b4 Panagiotis Issaris
    case dv_audio_recdate:
142
    case dv_video_recdate:  /* VAUX recording date */
143 4e92dabf Roman Shaposhnik
        ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
144 f94036f1 Diego Biurrun
                                            c->sys->time_base.den, AV_ROUND_DOWN);
145 bc60f09b Reimar Döffinger
        brktimegm(ct, &tc);
146
        buf[1] = 0xff; /* ds, tm, tens of time zone, units of time zone */
147
                       /* 0xff is very likely to be "unknown" */
148
        buf[2] = (3 << 6) | /* reserved -- always 1 */
149
                 ((tc.tm_mday / 10) << 4) | /* Tens of day */
150
                 (tc.tm_mday % 10);         /* Units of day */
151
        buf[3] = /* we set high 4 bits to 0, shouldn't we set them to week? */
152
                 ((tc.tm_mon / 10) << 4) |    /* Tens of month */
153
                 (tc.tm_mon  % 10);           /* Units of month */
154
        buf[4] = (((tc.tm_year % 100) / 10) << 4) | /* Tens of year */
155
                 (tc.tm_year % 10);                 /* Units of year */
156
        break;
157 d4fc91b4 Panagiotis Issaris
    case dv_audio_rectime:  /* AAUX recording time */
158
    case dv_video_rectime:  /* VAUX recording time */
159 4e92dabf Roman Shaposhnik
        ct = c->start_time + av_rescale_rnd(c->frames, c->sys->time_base.num,
160
                                                       c->sys->time_base.den, AV_ROUND_DOWN);
161 bc60f09b Reimar Döffinger
        brktimegm(ct, &tc);
162
        buf[1] = (3 << 6) | /* reserved -- always 1 */
163
                 0x3f; /* tens of frame, units of frame: 0x3f - "unknown" ? */
164
        buf[2] = (1 << 7) | /* reserved -- always 1 */
165
                 ((tc.tm_sec / 10) << 4) | /* Tens of seconds */
166
                 (tc.tm_sec % 10);         /* Units of seconds */
167
        buf[3] = (1 << 7) | /* reserved -- always 1 */
168
                 ((tc.tm_min / 10) << 4) | /* Tens of minutes */
169
                 (tc.tm_min % 10);         /* Units of minutes */
170
        buf[4] = (3 << 6) | /* reserved -- always 1 */
171
                 ((tc.tm_hour / 10) << 4) | /* Tens of hours */
172
                 (tc.tm_hour % 10);         /* Units of hours */
173
        break;
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    default:
175 bc60f09b Reimar Döffinger
        buf[1] = buf[2] = buf[3] = buf[4] = 0xff;
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    }
177
    return 5;
178
}
179
180
static void dv_inject_audio(DVMuxContext *c, int channel, uint8_t* frame_ptr)
181
{
182
    int i, j, d, of, size;
183
    size = 4 * dv_audio_frame_size(c->sys, c->frames);
184
    frame_ptr += channel * c->sys->difseg_size * 150 * 80;
185
    for (i = 0; i < c->sys->difseg_size; i++) {
186 bc60f09b Reimar Döffinger
        frame_ptr += 6 * 80; /* skip DIF segment header */
187
        for (j = 0; j < 9; j++) {
188
            dv_write_pack(dv_aaux_packs_dist[i][j], c, &frame_ptr[3], i >= c->sys->difseg_size/2);
189
            for (d = 8; d < 80; d+=2) {
190
                of = c->sys->audio_shuffle[i][j] + (d - 8)/2 * c->sys->audio_stride;
191
                if (of*2 >= size)
192
                    continue;
193 d4fc91b4 Panagiotis Issaris
194 41dd680d Michael Niedermayer
                frame_ptr[d]   = av_fifo_peek(c->audio_data[channel], of*2+1); // FIXME: maybe we have to admit
195
                frame_ptr[d+1] = av_fifo_peek(c->audio_data[channel], of*2);   //        that DV is a big-endian PCM
196 bc60f09b Reimar Döffinger
            }
197
            frame_ptr += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
198
        }
199 d4fc91b4 Panagiotis Issaris
    }
200
}
201
202
static void dv_inject_metadata(DVMuxContext *c, uint8_t* frame)
203
{
204
    int j, k;
205
    uint8_t* buf;
206
207
    for (buf = frame; buf < frame + c->sys->frame_size; buf += 150 * 80) {
208
        /* DV subcode: 2nd and 3d DIFs */
209
        for (j = 80; j < 80 * 3; j += 80) {
210
            for (k = 6; k < 6 * 8; k += 8)
211
                dv_write_pack(dv_timecode, c, &buf[j+k]);
212
213
            if (((long)(buf-frame)/(c->sys->frame_size/(c->sys->difseg_size*c->sys->n_difchan))%c->sys->difseg_size) > 5) { /* FIXME: is this really needed ? */
214
                dv_write_pack(dv_video_recdate, c, &buf[j+14]);
215
                dv_write_pack(dv_video_rectime, c, &buf[j+22]);
216
                dv_write_pack(dv_video_recdate, c, &buf[j+38]);
217
                dv_write_pack(dv_video_rectime, c, &buf[j+46]);
218
            }
219
        }
220
221
        /* DV VAUX: 4th, 5th and 6th 3DIFs */
222
        for (j = 80*3 + 3; j < 80*6; j += 80) {
223
            dv_write_pack(dv_video_recdate, c, &buf[j+5*2]);
224
            dv_write_pack(dv_video_rectime, c, &buf[j+5*3]);
225
            dv_write_pack(dv_video_recdate, c, &buf[j+5*11]);
226
            dv_write_pack(dv_video_rectime, c, &buf[j+5*12]);
227
        }
228
    }
229
}
230
231
/*
232
 * The following 3 functions constitute our interface to the world
233
 */
234
235 f0a86769 Diego Elio Pettenò
static int dv_assemble_frame(DVMuxContext *c, AVStream* st,
236
                             uint8_t* data, int data_size, uint8_t** frame)
237 d4fc91b4 Panagiotis Issaris
{
238
    int i, reqasize;
239
240
    *frame = &c->frame_buf[0];
241
    reqasize = 4 * dv_audio_frame_size(c->sys, c->frames);
242
243
    switch (st->codec->codec_type) {
244 72415b2a Stefano Sabatini
    case AVMEDIA_TYPE_VIDEO:
245 bc60f09b Reimar Döffinger
        /* FIXME: we have to have more sensible approach than this one */
246
        if (c->has_video)
247
            av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient audio data or severe sync problem.\n", c->frames);
248 d4fc91b4 Panagiotis Issaris
249 bc60f09b Reimar Döffinger
        memcpy(*frame, data, c->sys->frame_size);
250
        c->has_video = 1;
251
        break;
252 72415b2a Stefano Sabatini
    case AVMEDIA_TYPE_AUDIO:
253 bc60f09b Reimar Döffinger
        for (i = 0; i < c->n_ast && st != c->ast[i]; i++);
254 d4fc91b4 Panagiotis Issaris
255
          /* FIXME: we have to have more sensible approach than this one */
256 41dd680d Michael Niedermayer
        if (av_fifo_size(c->audio_data[i]) + data_size >= 100*AVCODEC_MAX_AUDIO_FRAME_SIZE)
257 bc60f09b Reimar Döffinger
            av_log(st->codec, AV_LOG_ERROR, "Can't process DV frame #%d. Insufficient video data or severe sync problem.\n", c->frames);
258 41dd680d Michael Niedermayer
        av_fifo_generic_write(c->audio_data[i], data, data_size, NULL);
259 d4fc91b4 Panagiotis Issaris
260 ca74c0a1 Diego Biurrun
        /* Let us see if we've got enough audio for one DV frame. */
261 41dd680d Michael Niedermayer
        c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
262 d4fc91b4 Panagiotis Issaris
263 bc60f09b Reimar Döffinger
        break;
264 d4fc91b4 Panagiotis Issaris
    default:
265 bc60f09b Reimar Döffinger
        break;
266 d4fc91b4 Panagiotis Issaris
    }
267
268 ca74c0a1 Diego Biurrun
    /* Let us see if we have enough data to construct one DV frame. */
269 f94036f1 Diego Biurrun
    if (c->has_video == 1 && c->has_audio + 1 == 1 << c->n_ast) {
270 d4fc91b4 Panagiotis Issaris
        dv_inject_metadata(c, *frame);
271 2e374f12 Corey Hickey
        c->has_audio = 0;
272 f94036f1 Diego Biurrun
        for (i=0; i < c->n_ast; i++) {
273 bc60f09b Reimar Döffinger
            dv_inject_audio(c, i, *frame);
274 41dd680d Michael Niedermayer
            av_fifo_drain(c->audio_data[i], reqasize);
275
            c->has_audio |= ((reqasize <= av_fifo_size(c->audio_data[i])) << i);
276 d4fc91b4 Panagiotis Issaris
        }
277
278
        c->has_video = 0;
279 2e374f12 Corey Hickey
280 d4fc91b4 Panagiotis Issaris
        c->frames++;
281
282
        return c->sys->frame_size;
283
    }
284
285
    return 0;
286
}
287
288 f0a86769 Diego Elio Pettenò
static DVMuxContext* dv_init_mux(AVFormatContext* s)
289 d4fc91b4 Panagiotis Issaris
{
290 e4141433 Nicholas Tung
    DVMuxContext *c = s->priv_data;
291 d4fc91b4 Panagiotis Issaris
    AVStream *vst = NULL;
292
    int i;
293
294
    /* we support at most 1 video and 2 audio streams */
295
    if (s->nb_streams > 3)
296
        return NULL;
297
298 f94036f1 Diego Biurrun
    c->n_ast  = 0;
299 d4fc91b4 Panagiotis Issaris
    c->ast[0] = c->ast[1] = NULL;
300
301
    /* We have to sort out where audio and where video stream is */
302
    for (i=0; i<s->nb_streams; i++) {
303 bc60f09b Reimar Döffinger
        switch (s->streams[i]->codec->codec_type) {
304 72415b2a Stefano Sabatini
        case AVMEDIA_TYPE_VIDEO:
305 bc60f09b Reimar Döffinger
            if (vst) return NULL;
306
            vst = s->streams[i];
307
            break;
308 72415b2a Stefano Sabatini
        case AVMEDIA_TYPE_AUDIO:
309 bc60f09b Reimar Döffinger
            if (c->n_ast > 1) return NULL;
310
            c->ast[c->n_ast++] = s->streams[i];
311
            break;
312
        default:
313
            goto bail_out;
314
        }
315 d4fc91b4 Panagiotis Issaris
    }
316
317
    /* Some checks -- DV format is very picky about its incoming streams */
318
    if (!vst || vst->codec->codec_id != CODEC_ID_DVVIDEO)
319
        goto bail_out;
320
    for (i=0; i<c->n_ast; i++) {
321 f94036f1 Diego Biurrun
        if (c->ast[i] && (c->ast[i]->codec->codec_id    != CODEC_ID_PCM_S16LE ||
322 d4fc91b4 Panagiotis Issaris
                          c->ast[i]->codec->sample_rate != 48000 ||
323 f94036f1 Diego Biurrun
                          c->ast[i]->codec->channels    != 2))
324 d4fc91b4 Panagiotis Issaris
            goto bail_out;
325
    }
326 c76911bd Reimar Döffinger
    c->sys = ff_dv_codec_profile(vst->codec);
327 d4fc91b4 Panagiotis Issaris
    if (!c->sys)
328
        goto bail_out;
329
330 f94036f1 Diego Biurrun
    if ((c->n_ast > 1) && (c->sys->n_difchan < 2)) {
331 d4fc91b4 Panagiotis Issaris
        /* only 1 stereo pair is allowed in 25Mbps mode */
332
        goto bail_out;
333
    }
334
335
    /* Ok, everything seems to be in working order */
336 f94036f1 Diego Biurrun
    c->frames     = 0;
337
    c->has_audio  = 0;
338
    c->has_video  = 0;
339 d4fc91b4 Panagiotis Issaris
    c->start_time = (time_t)s->timestamp;
340
341 f94036f1 Diego Biurrun
    for (i=0; i < c->n_ast; i++) {
342 41dd680d Michael Niedermayer
        if (c->ast[i] && !(c->audio_data[i]=av_fifo_alloc(100*AVCODEC_MAX_AUDIO_FRAME_SIZE))) {
343 f94036f1 Diego Biurrun
            while (i > 0) {
344 d4fc91b4 Panagiotis Issaris
                i--;
345 41dd680d Michael Niedermayer
                av_fifo_free(c->audio_data[i]);
346 d4fc91b4 Panagiotis Issaris
            }
347
            goto bail_out;
348
        }
349
    }
350
351
    return c;
352
353
bail_out:
354
    return NULL;
355
}
356
357 f0a86769 Diego Elio Pettenò
static void dv_delete_mux(DVMuxContext *c)
358 d4fc91b4 Panagiotis Issaris
{
359
    int i;
360
    for (i=0; i < c->n_ast; i++)
361 41dd680d Michael Niedermayer
        av_fifo_free(c->audio_data[i]);
362 d4fc91b4 Panagiotis Issaris
}
363
364
static int dv_write_header(AVFormatContext *s)
365
{
366 0008afc5 Brian Brice
    if (!dv_init_mux(s)) {
367 d4fc91b4 Panagiotis Issaris
        av_log(s, AV_LOG_ERROR, "Can't initialize DV format!\n"
368
                    "Make sure that you supply exactly two streams:\n"
369 910f02a0 Diego Biurrun
                    "     video: 25fps or 29.97fps, audio: 2ch/48kHz/PCM\n"
370 d4fc91b4 Panagiotis Issaris
                    "     (50Mbps allows an optional second audio stream)\n");
371
        return -1;
372
    }
373
    return 0;
374
}
375
376
static int dv_write_packet(struct AVFormatContext *s, AVPacket *pkt)
377
{
378
    uint8_t* frame;
379
    int fsize;
380
381 e4141433 Nicholas Tung
    fsize = dv_assemble_frame(s->priv_data, s->streams[pkt->stream_index],
382 d4fc91b4 Panagiotis Issaris
                              pkt->data, pkt->size, &frame);
383
    if (fsize > 0) {
384 899681cd Björn Axelsson
        put_buffer(s->pb, frame, fsize);
385
        put_flush_packet(s->pb);
386 d4fc91b4 Panagiotis Issaris
    }
387
    return 0;
388
}
389
390
/*
391
 * We might end up with some extra A/V data without matching counterpart.
392
 * E.g. video data without enough audio to write the complete frame.
393
 * Currently we simply drop the last frame. I don't know whether this
394
 * is the best strategy of all
395
 */
396
static int dv_write_trailer(struct AVFormatContext *s)
397
{
398 e4141433 Nicholas Tung
    dv_delete_mux(s->priv_data);
399 d4fc91b4 Panagiotis Issaris
    return 0;
400
}
401
402
AVOutputFormat dv_muxer = {
403
    "dv",
404 bde15e74 Stefano Sabatini
    NULL_IF_CONFIG_SMALL("DV video format"),
405 d4fc91b4 Panagiotis Issaris
    NULL,
406
    "dv",
407
    sizeof(DVMuxContext),
408
    CODEC_ID_PCM_S16LE,
409
    CODEC_ID_DVVIDEO,
410
    dv_write_header,
411
    dv_write_packet,
412
    dv_write_trailer,
413
};