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ffmpeg / libavformat / swfenc.c @ 470bce2b

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/*
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 * Flash Compatible Streaming Format muxer
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 * Copyright (c) 2000 Fabrice Bellard.
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 * Copyright (c) 2003 Tinic Uro.
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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
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 * 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
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#include "libavcodec/bitstream.h"
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#include "avformat.h"
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#include "swf.h"
26

    
27
static void put_swf_tag(AVFormatContext *s, int tag)
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{
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    SWFContext *swf = s->priv_data;
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    ByteIOContext *pb = s->pb;
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    swf->tag_pos = url_ftell(pb);
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    swf->tag = tag;
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    /* reserve some room for the tag */
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    if (tag & TAG_LONG) {
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        put_le16(pb, 0);
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        put_le32(pb, 0);
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    } else {
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        put_le16(pb, 0);
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    }
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}
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static void put_swf_end_tag(AVFormatContext *s)
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{
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    SWFContext *swf = s->priv_data;
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    ByteIOContext *pb = s->pb;
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    int64_t pos;
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    int tag_len, tag;
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    pos = url_ftell(pb);
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    tag_len = pos - swf->tag_pos - 2;
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    tag = swf->tag;
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    url_fseek(pb, swf->tag_pos, SEEK_SET);
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    if (tag & TAG_LONG) {
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        tag &= ~TAG_LONG;
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        put_le16(pb, (tag << 6) | 0x3f);
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        put_le32(pb, tag_len - 4);
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    } else {
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        assert(tag_len < 0x3f);
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        put_le16(pb, (tag << 6) | tag_len);
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    }
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    url_fseek(pb, pos, SEEK_SET);
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}
64

    
65
static inline void max_nbits(int *nbits_ptr, int val)
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{
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    int n;
68

    
69
    if (val == 0)
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        return;
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    val = abs(val);
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    n = 1;
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    while (val != 0) {
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        n++;
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        val >>= 1;
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    }
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    if (n > *nbits_ptr)
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        *nbits_ptr = n;
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}
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static void put_swf_rect(ByteIOContext *pb,
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                         int xmin, int xmax, int ymin, int ymax)
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{
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    PutBitContext p;
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    uint8_t buf[256];
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    int nbits, mask;
87

    
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    init_put_bits(&p, buf, sizeof(buf));
89

    
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    nbits = 0;
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    max_nbits(&nbits, xmin);
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    max_nbits(&nbits, xmax);
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    max_nbits(&nbits, ymin);
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    max_nbits(&nbits, ymax);
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    mask = (1 << nbits) - 1;
96

    
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    /* rectangle info */
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    put_bits(&p, 5, nbits);
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    put_bits(&p, nbits, xmin & mask);
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    put_bits(&p, nbits, xmax & mask);
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    put_bits(&p, nbits, ymin & mask);
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    put_bits(&p, nbits, ymax & mask);
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    flush_put_bits(&p);
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    put_buffer(pb, buf, pbBufPtr(&p) - p.buf);
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}
107

    
108
static void put_swf_line_edge(PutBitContext *pb, int dx, int dy)
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{
110
    int nbits, mask;
111

    
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    put_bits(pb, 1, 1); /* edge */
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    put_bits(pb, 1, 1); /* line select */
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    nbits = 2;
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    max_nbits(&nbits, dx);
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    max_nbits(&nbits, dy);
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118
    mask = (1 << nbits) - 1;
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    put_bits(pb, 4, nbits - 2); /* 16 bits precision */
120
    if (dx == 0) {
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        put_bits(pb, 1, 0);
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        put_bits(pb, 1, 1);
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        put_bits(pb, nbits, dy & mask);
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    } else if (dy == 0) {
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        put_bits(pb, 1, 0);
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        put_bits(pb, 1, 0);
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        put_bits(pb, nbits, dx & mask);
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    } else {
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        put_bits(pb, 1, 1);
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        put_bits(pb, nbits, dx & mask);
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        put_bits(pb, nbits, dy & mask);
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    }
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}
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#define FRAC_BITS 16
136

    
137
static void put_swf_matrix(ByteIOContext *pb,
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                           int a, int b, int c, int d, int tx, int ty)
139
{
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    PutBitContext p;
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    uint8_t buf[256];
142
    int nbits;
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    init_put_bits(&p, buf, sizeof(buf));
145

    
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    put_bits(&p, 1, 1); /* a, d present */
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    nbits = 1;
148
    max_nbits(&nbits, a);
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    max_nbits(&nbits, d);
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    put_bits(&p, 5, nbits); /* nb bits */
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    put_bits(&p, nbits, a);
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    put_bits(&p, nbits, d);
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154
    put_bits(&p, 1, 1); /* b, c present */
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    nbits = 1;
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    max_nbits(&nbits, c);
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    max_nbits(&nbits, b);
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    put_bits(&p, 5, nbits); /* nb bits */
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    put_bits(&p, nbits, c);
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    put_bits(&p, nbits, b);
161

    
162
    nbits = 1;
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    max_nbits(&nbits, tx);
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    max_nbits(&nbits, ty);
165
    put_bits(&p, 5, nbits); /* nb bits */
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    put_bits(&p, nbits, tx);
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    put_bits(&p, nbits, ty);
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169
    flush_put_bits(&p);
170
    put_buffer(pb, buf, pbBufPtr(&p) - p.buf);
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}
172

    
173
static int swf_write_header(AVFormatContext *s)
174
{
175
    SWFContext *swf = s->priv_data;
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    ByteIOContext *pb = s->pb;
177
    PutBitContext p;
178
    uint8_t buf1[256];
179
    int i, width, height, rate, rate_base;
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    int version;
181

    
182
    swf->sound_samples = 0;
183
    swf->swf_frame_number = 0;
184
    swf->video_frame_number = 0;
185

    
186
    for(i=0;i<s->nb_streams;i++) {
187
        AVCodecContext *enc = s->streams[i]->codec;
188
        if (enc->codec_type == CODEC_TYPE_AUDIO) {
189
            if (enc->codec_id == CODEC_ID_MP3) {
190
                if (!enc->frame_size) {
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                    av_log(s, AV_LOG_ERROR, "audio frame size not set\n");
192
                    return -1;
193
                }
194
                swf->audio_enc = enc;
195
                av_fifo_init(&swf->audio_fifo, AUDIO_FIFO_SIZE);
196
            } else {
197
                av_log(s, AV_LOG_ERROR, "SWF muxer only supports MP3\n");
198
                return -1;
199
            }
200
        } else {
201
            if (enc->codec_id == CODEC_ID_VP6F ||
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                enc->codec_id == CODEC_ID_FLV1 ||
203
                enc->codec_id == CODEC_ID_MJPEG) {
204
                swf->video_enc = enc;
205
            } else {
206
                av_log(s, AV_LOG_ERROR, "SWF muxer only supports VP6, FLV1 and MJPEG\n");
207
                return -1;
208
            }
209
        }
210
    }
211

    
212
    if (!swf->video_enc) {
213
        /* currently, cannot work correctly if audio only */
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        width = 320;
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        height = 200;
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        rate = 10;
217
        rate_base= 1;
218
    } else {
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        width = swf->video_enc->width;
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        height = swf->video_enc->height;
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        rate = swf->video_enc->time_base.den;
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        rate_base = swf->video_enc->time_base.num;
223
    }
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225
    if (!swf->audio_enc)
226
        swf->samples_per_frame = (44100. * rate_base) / rate;
227
    else
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        swf->samples_per_frame = (swf->audio_enc->sample_rate * rate_base) / rate;
229

    
230
    put_tag(pb, "FWS");
231

    
232
    if (!strcmp("avm2", s->oformat->name))
233
        version = 9;
234
    else if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_VP6F)
235
        version = 8; /* version 8 and above support VP6 codec */
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    else if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_FLV1)
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        version = 6; /* version 6 and above support FLV1 codec */
238
    else
239
        version = 4; /* version 4 for mpeg audio support */
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    put_byte(pb, version);
241

    
242
    put_le32(pb, DUMMY_FILE_SIZE); /* dummy size
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                                      (will be patched if not streamed) */
244

    
245
    put_swf_rect(pb, 0, width * 20, 0, height * 20);
246
    put_le16(pb, (rate * 256) / rate_base); /* frame rate */
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    swf->duration_pos = url_ftell(pb);
248
    put_le16(pb, (uint16_t)(DUMMY_DURATION * (int64_t)rate / rate_base)); /* frame count */
249

    
250
    /* avm2/swf v9 (also v8?) files require a file attribute tag */
251
    if (version == 9) {
252
        put_swf_tag(s, TAG_FILEATTRIBUTES);
253
        put_le32(pb, 1<<3); /* set ActionScript v3/AVM2 flag */
254
        put_swf_end_tag(s);
255
    }
256

    
257
    /* define a shape with the jpeg inside */
258
    if (swf->video_enc && swf->video_enc->codec_id == CODEC_ID_MJPEG) {
259
        put_swf_tag(s, TAG_DEFINESHAPE);
260

    
261
        put_le16(pb, SHAPE_ID); /* ID of shape */
262
        /* bounding rectangle */
263
        put_swf_rect(pb, 0, width, 0, height);
264
        /* style info */
265
        put_byte(pb, 1); /* one fill style */
266
        put_byte(pb, 0x41); /* clipped bitmap fill */
267
        put_le16(pb, BITMAP_ID); /* bitmap ID */
268
        /* position of the bitmap */
269
        put_swf_matrix(pb, (int)(1.0 * (1 << FRAC_BITS)), 0,
270
                       0, (int)(1.0 * (1 << FRAC_BITS)), 0, 0);
271
        put_byte(pb, 0); /* no line style */
272

    
273
        /* shape drawing */
274
        init_put_bits(&p, buf1, sizeof(buf1));
275
        put_bits(&p, 4, 1); /* one fill bit */
276
        put_bits(&p, 4, 0); /* zero line bit */
277

    
278
        put_bits(&p, 1, 0); /* not an edge */
279
        put_bits(&p, 5, FLAG_MOVETO | FLAG_SETFILL0);
280
        put_bits(&p, 5, 1); /* nbits */
281
        put_bits(&p, 1, 0); /* X */
282
        put_bits(&p, 1, 0); /* Y */
283
        put_bits(&p, 1, 1); /* set fill style 1 */
284

    
285
        /* draw the rectangle ! */
286
        put_swf_line_edge(&p, width, 0);
287
        put_swf_line_edge(&p, 0, height);
288
        put_swf_line_edge(&p, -width, 0);
289
        put_swf_line_edge(&p, 0, -height);
290

    
291
        /* end of shape */
292
        put_bits(&p, 1, 0); /* not an edge */
293
        put_bits(&p, 5, 0);
294

    
295
        flush_put_bits(&p);
296
        put_buffer(pb, buf1, pbBufPtr(&p) - p.buf);
297

    
298
        put_swf_end_tag(s);
299
    }
300

    
301
    if (swf->audio_enc && swf->audio_enc->codec_id == CODEC_ID_MP3) {
302
        int v = 0;
303

    
304
        /* start sound */
305
        put_swf_tag(s, TAG_STREAMHEAD2);
306
        switch(swf->audio_enc->sample_rate) {
307
        case 11025: v |= 1 << 2; break;
308
        case 22050: v |= 2 << 2; break;
309
        case 44100: v |= 3 << 2; break;
310
        default:
311
            /* not supported */
312
            av_log(s, AV_LOG_ERROR, "swf does not support that sample rate, choose from (44100, 22050, 11025).\n");
313
            return -1;
314
        }
315
        v |= 0x02; /* 16 bit playback */
316
        if (swf->audio_enc->channels == 2)
317
            v |= 0x01; /* stereo playback */
318
        put_byte(s->pb, v);
319
        v |= 0x20; /* mp3 compressed */
320
        put_byte(s->pb, v);
321
        put_le16(s->pb, swf->samples_per_frame);  /* avg samples per frame */
322
        put_le16(s->pb, 0);
323

    
324
        put_swf_end_tag(s);
325
    }
326

    
327
    put_flush_packet(s->pb);
328
    return 0;
329
}
330

    
331
static int swf_write_video(AVFormatContext *s,
332
                           AVCodecContext *enc, const uint8_t *buf, int size)
333
{
334
    SWFContext *swf = s->priv_data;
335
    ByteIOContext *pb = s->pb;
336

    
337
    /* Flash Player limit */
338
    if (swf->swf_frame_number == 16000)
339
        av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
340

    
341
    if (enc->codec_id == CODEC_ID_VP6F ||
342
        enc->codec_id == CODEC_ID_FLV1) {
343
        if (swf->video_frame_number == 0) {
344
            /* create a new video object */
345
            put_swf_tag(s, TAG_VIDEOSTREAM);
346
            put_le16(pb, VIDEO_ID);
347
            swf->vframes_pos = url_ftell(pb);
348
            put_le16(pb, 15000); /* hard flash player limit */
349
            put_le16(pb, enc->width);
350
            put_le16(pb, enc->height);
351
            put_byte(pb, 0);
352
            put_byte(pb,codec_get_tag(swf_codec_tags,enc->codec_id));
353
            put_swf_end_tag(s);
354

    
355
            /* place the video object for the first time */
356
            put_swf_tag(s, TAG_PLACEOBJECT2);
357
            put_byte(pb, 0x36);
358
            put_le16(pb, 1);
359
            put_le16(pb, VIDEO_ID);
360
            put_swf_matrix(pb, 1 << FRAC_BITS, 0, 0, 1 << FRAC_BITS, 0, 0);
361
            put_le16(pb, swf->video_frame_number);
362
            put_tag(pb, "video");
363
            put_byte(pb, 0x00);
364
            put_swf_end_tag(s);
365
        } else {
366
            /* mark the character for update */
367
            put_swf_tag(s, TAG_PLACEOBJECT2);
368
            put_byte(pb, 0x11);
369
            put_le16(pb, 1);
370
            put_le16(pb, swf->video_frame_number);
371
            put_swf_end_tag(s);
372
        }
373

    
374
        /* set video frame data */
375
        put_swf_tag(s, TAG_VIDEOFRAME | TAG_LONG);
376
        put_le16(pb, VIDEO_ID);
377
        put_le16(pb, swf->video_frame_number++);
378
        put_buffer(pb, buf, size);
379
        put_swf_end_tag(s);
380
    } else if (enc->codec_id == CODEC_ID_MJPEG) {
381
        if (swf->swf_frame_number > 0) {
382
            /* remove the shape */
383
            put_swf_tag(s, TAG_REMOVEOBJECT);
384
            put_le16(pb, SHAPE_ID); /* shape ID */
385
            put_le16(pb, 1); /* depth */
386
            put_swf_end_tag(s);
387

    
388
            /* free the bitmap */
389
            put_swf_tag(s, TAG_FREECHARACTER);
390
            put_le16(pb, BITMAP_ID);
391
            put_swf_end_tag(s);
392
        }
393

    
394
        put_swf_tag(s, TAG_JPEG2 | TAG_LONG);
395

    
396
        put_le16(pb, BITMAP_ID); /* ID of the image */
397

    
398
        /* a dummy jpeg header seems to be required */
399
        put_be32(pb, 0xffd8ffd9);
400
        /* write the jpeg image */
401
        put_buffer(pb, buf, size);
402

    
403
        put_swf_end_tag(s);
404

    
405
        /* draw the shape */
406

    
407
        put_swf_tag(s, TAG_PLACEOBJECT);
408
        put_le16(pb, SHAPE_ID); /* shape ID */
409
        put_le16(pb, 1); /* depth */
410
        put_swf_matrix(pb, 20 << FRAC_BITS, 0, 0, 20 << FRAC_BITS, 0, 0);
411
        put_swf_end_tag(s);
412
    }
413

    
414
    swf->swf_frame_number++;
415

    
416
    /* streaming sound always should be placed just before showframe tags */
417
    if (swf->audio_enc && av_fifo_size(&swf->audio_fifo)) {
418
        int frame_size = av_fifo_size(&swf->audio_fifo);
419
        put_swf_tag(s, TAG_STREAMBLOCK | TAG_LONG);
420
        put_le16(pb, swf->sound_samples);
421
        put_le16(pb, 0); // seek samples
422
        av_fifo_generic_read(&swf->audio_fifo, frame_size, &put_buffer, pb);
423
        put_swf_end_tag(s);
424

    
425
        /* update FIFO */
426
        swf->sound_samples = 0;
427
    }
428

    
429
    /* output the frame */
430
    put_swf_tag(s, TAG_SHOWFRAME);
431
    put_swf_end_tag(s);
432

    
433
    put_flush_packet(s->pb);
434

    
435
    return 0;
436
}
437

    
438
static int swf_write_audio(AVFormatContext *s,
439
                           AVCodecContext *enc, const uint8_t *buf, int size)
440
{
441
    SWFContext *swf = s->priv_data;
442

    
443
    /* Flash Player limit */
444
    if (swf->swf_frame_number == 16000)
445
        av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
446

    
447
    if (av_fifo_size(&swf->audio_fifo) + size > AUDIO_FIFO_SIZE) {
448
        av_log(s, AV_LOG_ERROR, "audio fifo too small to mux audio essence\n");
449
        return -1;
450
    }
451

    
452
    av_fifo_generic_write(&swf->audio_fifo, buf, size, NULL);
453
    swf->sound_samples += enc->frame_size;
454

    
455
    /* if audio only stream make sure we add swf frames */
456
    if (!swf->video_enc)
457
        swf_write_video(s, enc, 0, 0);
458

    
459
    return 0;
460
}
461

    
462
static int swf_write_packet(AVFormatContext *s, AVPacket *pkt)
463
{
464
    AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
465
    if (codec->codec_type == CODEC_TYPE_AUDIO)
466
        return swf_write_audio(s, codec, pkt->data, pkt->size);
467
    else
468
        return swf_write_video(s, codec, pkt->data, pkt->size);
469
}
470

    
471
static int swf_write_trailer(AVFormatContext *s)
472
{
473
    SWFContext *swf = s->priv_data;
474
    ByteIOContext *pb = s->pb;
475
    AVCodecContext *enc, *video_enc;
476
    int file_size, i;
477

    
478
    video_enc = NULL;
479
    for(i=0;i<s->nb_streams;i++) {
480
        enc = s->streams[i]->codec;
481
        if (enc->codec_type == CODEC_TYPE_VIDEO)
482
            video_enc = enc;
483
        else
484
            av_fifo_free(&swf->audio_fifo);
485
    }
486

    
487
    put_swf_tag(s, TAG_END);
488
    put_swf_end_tag(s);
489

    
490
    put_flush_packet(s->pb);
491

    
492
    /* patch file size and number of frames if not streamed */
493
    if (!url_is_streamed(s->pb) && video_enc) {
494
        file_size = url_ftell(pb);
495
        url_fseek(pb, 4, SEEK_SET);
496
        put_le32(pb, file_size);
497
        url_fseek(pb, swf->duration_pos, SEEK_SET);
498
        put_le16(pb, swf->video_frame_number);
499
        url_fseek(pb, swf->vframes_pos, SEEK_SET);
500
        put_le16(pb, swf->video_frame_number);
501
        url_fseek(pb, file_size, SEEK_SET);
502
    }
503
    return 0;
504
}
505

    
506
#ifdef CONFIG_SWF_MUXER
507
AVOutputFormat swf_muxer = {
508
    "swf",
509
    NULL_IF_CONFIG_SMALL("Flash format"),
510
    "application/x-shockwave-flash",
511
    "swf",
512
    sizeof(SWFContext),
513
    CODEC_ID_MP3,
514
    CODEC_ID_FLV1,
515
    swf_write_header,
516
    swf_write_packet,
517
    swf_write_trailer,
518
};
519
#endif
520
#ifdef CONFIG_AVM2_MUXER
521
AVOutputFormat avm2_muxer = {
522
    "avm2",
523
    NULL_IF_CONFIG_SMALL("Flash 9 (AVM2) format"),
524
    "application/x-shockwave-flash",
525
    NULL,
526
    sizeof(SWFContext),
527
    CODEC_ID_MP3,
528
    CODEC_ID_FLV1,
529
    swf_write_header,
530
    swf_write_packet,
531
    swf_write_trailer,
532
};
533
#endif