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/*
* Flash Compatible Streaming Format muxer
* Copyright (c) 2000 Fabrice Bellard.
* Copyright (c) 2003 Tinic Uro.
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavcodec/bitstream.h"
#include "avformat.h"
#include "swf.h"
static void put_swf_tag(AVFormatContext *s, int tag)
{
SWFContext *swf = s->priv_data;
ByteIOContext *pb = s->pb;
swf->tag_pos = url_ftell(pb);
swf->tag = tag;
/* reserve some room for the tag */
if (tag & TAG_LONG) {
put_le16(pb, 0);
put_le32(pb, 0);
} else {
put_le16(pb, 0);
}
}
static void put_swf_end_tag(AVFormatContext *s)
{
SWFContext *swf = s->priv_data;
ByteIOContext *pb = s->pb;
offset_t pos;
int tag_len, tag;
pos = url_ftell(pb);
tag_len = pos - swf->tag_pos - 2;
tag = swf->tag;
url_fseek(pb, swf->tag_pos, SEEK_SET);
if (tag & TAG_LONG) {
tag &= ~TAG_LONG;
put_le16(pb, (tag << 6) | 0x3f);
put_le32(pb, tag_len - 4);
} else {
assert(tag_len < 0x3f);
put_le16(pb, (tag << 6) | tag_len);
}
url_fseek(pb, pos, SEEK_SET);
}
static inline void max_nbits(int *nbits_ptr, int val)
{
int n;
if (val == 0)
return;
val = abs(val);
n = 1;
while (val != 0) {
n++;
val >>= 1;
}
if (n > *nbits_ptr)
*nbits_ptr = n;
}
static void put_swf_rect(ByteIOContext *pb,
int xmin, int xmax, int ymin, int ymax)
{
PutBitContext p;
uint8_t buf[256];
int nbits, mask;
init_put_bits(&p, buf, sizeof(buf));
nbits = 0;
max_nbits(&nbits, xmin);
max_nbits(&nbits, xmax);
max_nbits(&nbits, ymin);
max_nbits(&nbits, ymax);
mask = (1 << nbits) - 1;
/* rectangle info */
put_bits(&p, 5, nbits);
put_bits(&p, nbits, xmin & mask);
put_bits(&p, nbits, xmax & mask);
put_bits(&p, nbits, ymin & mask);
put_bits(&p, nbits, ymax & mask);
flush_put_bits(&p);
put_buffer(pb, buf, pbBufPtr(&p) - p.buf);
}
static void put_swf_line_edge(PutBitContext *pb, int dx, int dy)
{
int nbits, mask;
put_bits(pb, 1, 1); /* edge */
put_bits(pb, 1, 1); /* line select */
nbits = 2;
max_nbits(&nbits, dx);
max_nbits(&nbits, dy);
mask = (1 << nbits) - 1;
put_bits(pb, 4, nbits - 2); /* 16 bits precision */
if (dx == 0) {
put_bits(pb, 1, 0);
put_bits(pb, 1, 1);
put_bits(pb, nbits, dy & mask);
} else if (dy == 0) {
put_bits(pb, 1, 0);
put_bits(pb, 1, 0);
put_bits(pb, nbits, dx & mask);
} else {
put_bits(pb, 1, 1);
put_bits(pb, nbits, dx & mask);
put_bits(pb, nbits, dy & mask);
}
}
#define FRAC_BITS 16
static void put_swf_matrix(ByteIOContext *pb,
int a, int b, int c, int d, int tx, int ty)
{
PutBitContext p;
uint8_t buf[256];
int nbits;
init_put_bits(&p, buf, sizeof(buf));
put_bits(&p, 1, 1); /* a, d present */
nbits = 1;
max_nbits(&nbits, a);
max_nbits(&nbits, d);
put_bits(&p, 5, nbits); /* nb bits */
put_bits(&p, nbits, a);
put_bits(&p, nbits, d);
put_bits(&p, 1, 1); /* b, c present */
nbits = 1;
max_nbits(&nbits, c);
max_nbits(&nbits, b);
put_bits(&p, 5, nbits); /* nb bits */
put_bits(&p, nbits, c);
put_bits(&p, nbits, b);
nbits = 1;
max_nbits(&nbits, tx);
max_nbits(&nbits, ty);
put_bits(&p, 5, nbits); /* nb bits */
put_bits(&p, nbits, tx);
put_bits(&p, nbits, ty);
flush_put_bits(&p);
put_buffer(pb, buf, pbBufPtr(&p) - p.buf);
}
static int swf_write_header(AVFormatContext *s)
{
SWFContext *swf = s->priv_data;
ByteIOContext *pb = s->pb;
AVCodecContext *enc, *audio_enc, *video_enc;
PutBitContext p;
uint8_t buf1[256];
int i, width, height, rate, rate_base;
int is_avm2;
swf->audio_in_pos = 0;
swf->sound_samples = 0;
swf->swf_frame_number = 0;
swf->video_frame_number = 0;
video_enc = NULL;
audio_enc = NULL;
for(i=0;i<s->nb_streams;i++) {
enc = s->streams[i]->codec;
if (enc->codec_type == CODEC_TYPE_AUDIO) {
if (enc->codec_id == CODEC_ID_MP3) {
if (!enc->frame_size) {
av_log(s, AV_LOG_ERROR, "audio frame size not set\n");
return -1;
}
audio_enc = enc;
} else {
av_log(s, AV_LOG_ERROR, "SWF muxer only supports MP3\n");
return -1;
}
} else {
if (enc->codec_id == CODEC_ID_VP6F ||
enc->codec_id == CODEC_ID_FLV1 ||
enc->codec_id == CODEC_ID_MJPEG) {
video_enc = enc;
} else {
av_log(s, AV_LOG_ERROR, "SWF muxer only supports VP6, FLV1 and MJPEG\n");
return -1;
}
}
}
if (!video_enc) {
/* currently, cannot work correctly if audio only */
swf->video_type = 0;
width = 320;
height = 200;
rate = 10;
rate_base= 1;
} else {
swf->video_type = video_enc->codec_id;
width = video_enc->width;
height = video_enc->height;
rate = video_enc->time_base.den;
rate_base = video_enc->time_base.num;
}
if (!audio_enc) {
swf->audio_type = 0;
swf->samples_per_frame = (44100. * rate_base) / rate;
} else {
swf->audio_type = audio_enc->codec_id;
swf->samples_per_frame = (audio_enc->sample_rate * rate_base) / rate;
}
is_avm2 = !strcmp("avm2", s->oformat->name);
put_tag(pb, "FWS");
if (is_avm2)
put_byte(pb, 9);
else if (video_enc && video_enc->codec_id == CODEC_ID_VP6F)
put_byte(pb, 8); /* version (version 8 and above support VP6 codec) */
else if (video_enc && video_enc->codec_id == CODEC_ID_FLV1)
put_byte(pb, 6); /* version (version 6 and above support FLV1 codec) */
else
put_byte(pb, 4); /* version (should use 4 for mpeg audio support) */
put_le32(pb, DUMMY_FILE_SIZE); /* dummy size
(will be patched if not streamed) */
put_swf_rect(pb, 0, width * 20, 0, height * 20);
put_le16(pb, (rate * 256) / rate_base); /* frame rate */
swf->duration_pos = url_ftell(pb);
put_le16(pb, (uint16_t)(DUMMY_DURATION * (int64_t)rate / rate_base)); /* frame count */
/* avm2/swf v9 (also v8?) files require a file attribute tag */
if (is_avm2) {
put_swf_tag(s, TAG_FILEATTRIBUTES);
put_le32(pb, 1<<3); /* set ActionScript v3/AVM2 flag */
put_swf_end_tag(s);
}
/* define a shape with the jpeg inside */
if (video_enc && video_enc->codec_id == CODEC_ID_MJPEG) {
put_swf_tag(s, TAG_DEFINESHAPE);
put_le16(pb, SHAPE_ID); /* ID of shape */
/* bounding rectangle */
put_swf_rect(pb, 0, width, 0, height);
/* style info */
put_byte(pb, 1); /* one fill style */
put_byte(pb, 0x41); /* clipped bitmap fill */
put_le16(pb, BITMAP_ID); /* bitmap ID */
/* position of the bitmap */
put_swf_matrix(pb, (int)(1.0 * (1 << FRAC_BITS)), 0,
0, (int)(1.0 * (1 << FRAC_BITS)), 0, 0);
put_byte(pb, 0); /* no line style */
/* shape drawing */
init_put_bits(&p, buf1, sizeof(buf1));
put_bits(&p, 4, 1); /* one fill bit */
put_bits(&p, 4, 0); /* zero line bit */
put_bits(&p, 1, 0); /* not an edge */
put_bits(&p, 5, FLAG_MOVETO | FLAG_SETFILL0);
put_bits(&p, 5, 1); /* nbits */
put_bits(&p, 1, 0); /* X */
put_bits(&p, 1, 0); /* Y */
put_bits(&p, 1, 1); /* set fill style 1 */
/* draw the rectangle ! */
put_swf_line_edge(&p, width, 0);
put_swf_line_edge(&p, 0, height);
put_swf_line_edge(&p, -width, 0);
put_swf_line_edge(&p, 0, -height);
/* end of shape */
put_bits(&p, 1, 0); /* not an edge */
put_bits(&p, 5, 0);
flush_put_bits(&p);
put_buffer(pb, buf1, pbBufPtr(&p) - p.buf);
put_swf_end_tag(s);
}
if (audio_enc && audio_enc->codec_id == CODEC_ID_MP3) {
int v;
/* start sound */
put_swf_tag(s, TAG_STREAMHEAD2);
v = 0;
switch(audio_enc->sample_rate) {
case 11025:
v |= 1 << 2;
break;
case 22050:
v |= 2 << 2;
break;
case 44100:
v |= 3 << 2;
break;
default:
/* not supported */
av_log(s, AV_LOG_ERROR, "swf does not support that sample rate, choose from (44100, 22050, 11025).\n");
return -1;
}
v |= 0x02; /* 16 bit playback */
if (audio_enc->channels == 2)
v |= 0x01; /* stereo playback */
put_byte(s->pb, v);
v |= 0x20; /* mp3 compressed */
put_byte(s->pb, v);
put_le16(s->pb, swf->samples_per_frame); /* avg samples per frame */
put_le16(s->pb, 0);
put_swf_end_tag(s);
}
put_flush_packet(s->pb);
return 0;
}
static int swf_write_video(AVFormatContext *s,
AVCodecContext *enc, const uint8_t *buf, int size)
{
SWFContext *swf = s->priv_data;
ByteIOContext *pb = s->pb;
/* Flash Player limit */
if (swf->swf_frame_number == 16000)
av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
if (swf->video_type == CODEC_ID_VP6F ||
swf->video_type == CODEC_ID_FLV1) {
if (swf->video_frame_number == 0) {
/* create a new video object */
put_swf_tag(s, TAG_VIDEOSTREAM);
put_le16(pb, VIDEO_ID);
put_le16(pb, 15000); /* hard flash player limit */
put_le16(pb, enc->width);
put_le16(pb, enc->height);
put_byte(pb, 0);
put_byte(pb,codec_get_tag(swf_codec_tags,swf->video_type));
put_swf_end_tag(s);
/* place the video object for the first time */
put_swf_tag(s, TAG_PLACEOBJECT2);
put_byte(pb, 0x36);
put_le16(pb, 1);
put_le16(pb, VIDEO_ID);
put_swf_matrix(pb, 1 << FRAC_BITS, 0, 0, 1 << FRAC_BITS, 0, 0);
put_le16(pb, swf->video_frame_number);
put_tag(pb, "video");
put_byte(pb, 0x00);
put_swf_end_tag(s);
} else {
/* mark the character for update */
put_swf_tag(s, TAG_PLACEOBJECT2);
put_byte(pb, 0x11);
put_le16(pb, 1);
put_le16(pb, swf->video_frame_number);
put_swf_end_tag(s);
}
/* set video frame data */
put_swf_tag(s, TAG_VIDEOFRAME | TAG_LONG);
put_le16(pb, VIDEO_ID);
put_le16(pb, swf->video_frame_number++);
put_buffer(pb, buf, size);
put_swf_end_tag(s);
} else if (swf->video_type == CODEC_ID_MJPEG) {
if (swf->swf_frame_number > 0) {
/* remove the shape */
put_swf_tag(s, TAG_REMOVEOBJECT);
put_le16(pb, SHAPE_ID); /* shape ID */
put_le16(pb, 1); /* depth */
put_swf_end_tag(s);
/* free the bitmap */
put_swf_tag(s, TAG_FREECHARACTER);
put_le16(pb, BITMAP_ID);
put_swf_end_tag(s);
}
put_swf_tag(s, TAG_JPEG2 | TAG_LONG);
put_le16(pb, BITMAP_ID); /* ID of the image */
/* a dummy jpeg header seems to be required */
put_byte(pb, 0xff);
put_byte(pb, 0xd8);
put_byte(pb, 0xff);
put_byte(pb, 0xd9);
/* write the jpeg image */
put_buffer(pb, buf, size);
put_swf_end_tag(s);
/* draw the shape */
put_swf_tag(s, TAG_PLACEOBJECT);
put_le16(pb, SHAPE_ID); /* shape ID */
put_le16(pb, 1); /* depth */
put_swf_matrix(pb, 20 << FRAC_BITS, 0, 0, 20 << FRAC_BITS, 0, 0);
put_swf_end_tag(s);
}
swf->swf_frame_number ++;
/* streaming sound always should be placed just before showframe tags */
if (swf->audio_type && swf->audio_in_pos) {
put_swf_tag(s, TAG_STREAMBLOCK | TAG_LONG);
put_le16(pb, swf->sound_samples);
put_le16(pb, 0); // seek samples
put_buffer(pb, swf->audio_fifo, swf->audio_in_pos);
put_swf_end_tag(s);
/* update FIFO */
swf->sound_samples = 0;
swf->audio_in_pos = 0;
}
/* output the frame */
put_swf_tag(s, TAG_SHOWFRAME);
put_swf_end_tag(s);
put_flush_packet(s->pb);
return 0;
}
static int swf_write_audio(AVFormatContext *s,
AVCodecContext *enc, const uint8_t *buf, int size)
{
SWFContext *swf = s->priv_data;
/* Flash Player limit */
if (swf->swf_frame_number == 16000)
av_log(enc, AV_LOG_INFO, "warning: Flash Player limit of 16000 frames reached\n");
if (swf->audio_in_pos + size >= AUDIO_FIFO_SIZE) {
av_log(s, AV_LOG_ERROR, "audio fifo too small to mux audio essence\n");
return -1;
}
memcpy(swf->audio_fifo + swf->audio_in_pos, buf, size);
swf->audio_in_pos += size;
swf->sound_samples += enc->frame_size;
/* if audio only stream make sure we add swf frames */
if (swf->video_type == 0)
swf_write_video(s, enc, 0, 0);
return 0;
}
static int swf_write_packet(AVFormatContext *s, AVPacket *pkt)
{
AVCodecContext *codec = s->streams[pkt->stream_index]->codec;
if (codec->codec_type == CODEC_TYPE_AUDIO)
return swf_write_audio(s, codec, pkt->data, pkt->size);
else
return swf_write_video(s, codec, pkt->data, pkt->size);
}
static int swf_write_trailer(AVFormatContext *s)
{
SWFContext *swf = s->priv_data;
ByteIOContext *pb = s->pb;
AVCodecContext *enc, *video_enc;
int file_size, i;
video_enc = NULL;
for(i=0;i<s->nb_streams;i++) {
enc = s->streams[i]->codec;
if (enc->codec_type == CODEC_TYPE_VIDEO)
video_enc = enc;
}
put_swf_tag(s, TAG_END);
put_swf_end_tag(s);
put_flush_packet(s->pb);
/* patch file size and number of frames if not streamed */
if (!url_is_streamed(s->pb) && video_enc) {
file_size = url_ftell(pb);
url_fseek(pb, 4, SEEK_SET);
put_le32(pb, file_size);
url_fseek(pb, swf->duration_pos, SEEK_SET);
put_le16(pb, video_enc->frame_number);
url_fseek(pb, file_size, SEEK_SET);
}
return 0;
}
#ifdef CONFIG_SWF_MUXER
AVOutputFormat swf_muxer = {
"swf",
"Flash format",
"application/x-shockwave-flash",
"swf",
sizeof(SWFContext),
CODEC_ID_MP3,
CODEC_ID_FLV1,
swf_write_header,
swf_write_packet,
swf_write_trailer,
};
#endif
#ifdef CONFIG_AVM2_MUXER
AVOutputFormat avm2_muxer = {
"avm2",
"Flash 9 (AVM2) format",
"application/x-shockwave-flash",
NULL,
sizeof(SWFContext),
CODEC_ID_MP3,
CODEC_ID_FLV1,
swf_write_header,
swf_write_packet,
swf_write_trailer,
};
#endif
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