From de6d9b6404bfd1c589799142da5a95428f146edd Mon Sep 17 00:00:00 2001 From: Fabrice Bellard Date: Sun, 22 Jul 2001 14:18:56 +0000 Subject: Initial revision Originally committed as revision 5 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libav/swf.c | 552 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 552 insertions(+) create mode 100644 libav/swf.c (limited to 'libav/swf.c') diff --git a/libav/swf.c b/libav/swf.c new file mode 100644 index 0000000000..a93c4f7097 --- /dev/null +++ b/libav/swf.c @@ -0,0 +1,552 @@ +/* + * Flash Compatible Streaming Format + * Copyright (c) 2000 Gerard Lantau. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ +#include +#include +#include +#include + +#include "avformat.h" + +#include + +/* should have a generic way to indicate probable size */ +#define DUMMY_FILE_SIZE (100 * 1024 * 1024) +#define DUMMY_DURATION 600 /* in seconds */ + +#define TAG_END 0 +#define TAG_SHOWFRAME 1 +#define TAG_DEFINESHAPE 2 +#define TAG_FREECHARACTER 3 +#define TAG_PLACEOBJECT 4 +#define TAG_REMOVEOBJECT 5 +#define TAG_STREAMHEAD 18 +#define TAG_STREAMBLOCK 19 +#define TAG_JPEG2 21 + +#define TAG_LONG 0x100 + +/* flags for shape definition */ +#define FLAG_MOVETO 0x01 +#define FLAG_SETFILL0 0x02 +#define FLAG_SETFILL1 0x04 + +/* character id used */ +#define BITMAP_ID 0 +#define SHAPE_ID 1 + +typedef struct { + long long duration_pos; + long long tag_pos; + int tag; +} SWFContext; + +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; + long long 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 buf[256]; + int nbits, mask; + + init_put_bits(&p, buf, sizeof(buf), NULL, NULL); + + 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, p.buf_ptr - 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 + +/* put matrix (not size optimized */ +static void put_swf_matrix(ByteIOContext *pb, + int a, int b, int c, int d, int tx, int ty) +{ + PutBitContext p; + UINT8 buf[256]; + + init_put_bits(&p, buf, sizeof(buf), NULL, NULL); + + put_bits(&p, 1, 1); /* a, d present */ + put_bits(&p, 5, 20); /* nb bits */ + put_bits(&p, 20, a); + put_bits(&p, 20, d); + + put_bits(&p, 1, 1); /* b, c present */ + put_bits(&p, 5, 20); /* nb bits */ + put_bits(&p, 20, c); + put_bits(&p, 20, b); + + put_bits(&p, 5, 20); /* nb bits */ + put_bits(&p, 20, tx); + put_bits(&p, 20, ty); + + flush_put_bits(&p); + put_buffer(pb, buf, p.buf_ptr - p.buf); +} + +/* XXX: handle audio only */ +static int swf_write_header(AVFormatContext *s) +{ + SWFContext *swf; + ByteIOContext *pb = &s->pb; + AVCodecContext *enc, *audio_enc, *video_enc; + PutBitContext p; + UINT8 buf1[256]; + int i, width, height, rate; + + swf = malloc(sizeof(SWFContext)); + if (!swf) + return -1; + s->priv_data = swf; + + video_enc = NULL; + audio_enc = NULL; + for(i=0;inb_streams;i++) { + enc = &s->streams[i]->codec; + if (enc->codec_type == CODEC_TYPE_AUDIO) + audio_enc = enc; + else + video_enc = enc; + } + + if (!video_enc) { + /* currenty, cannot work correctly if audio only */ + width = 320; + height = 200; + rate = 10 * FRAME_RATE_BASE; + } else { + width = video_enc->width; + height = video_enc->height; + rate = video_enc->frame_rate; + } + + put_tag(pb, "FWS"); + 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, 0, height); + put_le16(pb, (rate * 256) / FRAME_RATE_BASE); /* frame rate */ + swf->duration_pos = url_ftell(pb); + put_le16(pb, DUMMY_DURATION * (INT64)rate / FRAME_RATE_BASE); /* frame count */ + + /* define a shape with the jpeg inside */ + + 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), NULL, NULL); + 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, p.buf_ptr - p.buf); + + put_swf_end_tag(s); + + + if (audio_enc) { + int v; + + /* start sound */ + + 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 */ + free(swf); + return -1; + } + if (audio_enc->channels == 2) + v |= 1; + v |= 0x20; /* mp3 compressed */ + v |= 0x02; /* 16 bits */ + + put_swf_tag(s, TAG_STREAMHEAD); + put_byte(&s->pb, 0); + put_byte(&s->pb, v); + put_le16(&s->pb, (audio_enc->sample_rate * FRAME_RATE_BASE) / rate); /* avg samples per frame */ + + + put_swf_end_tag(s); + } + + put_flush_packet(&s->pb); + return 0; +} + +static int swf_write_video(AVFormatContext *s, + AVCodecContext *enc, UINT8 *buf, int size) +{ + ByteIOContext *pb = &s->pb; + static int tag_id = 0; + + if (enc->frame_number > 1) { + /* 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, tag_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, 1 << FRAC_BITS, 0, 0, 1 << FRAC_BITS, 0, 0); + put_swf_end_tag(s); + + /* 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, UINT8 *buf, int size) +{ + ByteIOContext *pb = &s->pb; + + put_swf_tag(s, TAG_STREAMBLOCK | TAG_LONG); + + put_buffer(pb, buf, size); + + put_swf_end_tag(s); + put_flush_packet(&s->pb); + return 0; +} + +static int swf_write_packet(AVFormatContext *s, int stream_index, + UINT8 *buf, int size) +{ + AVCodecContext *codec = &s->streams[stream_index]->codec; + if (codec->codec_type == CODEC_TYPE_AUDIO) + return swf_write_audio(s, buf, size); + else + return swf_write_video(s, codec, buf, 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;inb_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); + } + free(swf); + return 0; +} + +/***********************************/ +/* just to extract MP3 from swf */ + +static int get_swf_tag(ByteIOContext *pb, int *len_ptr) +{ + int tag, len; + + if (url_feof(pb)) + return -1; + + tag = get_le16(pb); + len = tag & 0x3f; + tag = tag >> 6; + if (len == 0x3f) { + len = get_le32(pb); + } + *len_ptr = len; + return tag; +} + +static int swf_read_header(AVFormatContext *s, AVFormatParameters *ap) +{ + ByteIOContext *pb = &s->pb; + int nbits, len, frame_rate, tag, v; + AVStream *st; + + if ((get_be32(pb) & 0xffffff00) != MKBETAG('F', 'W', 'S', 0)) + return -EIO; + get_le32(pb); + /* skip rectangle size */ + nbits = get_byte(pb) >> 3; + len = (4 * nbits - 3 + 7) / 8; + url_fskip(pb, len); + frame_rate = get_le16(pb); + get_le16(pb); /* frame count */ + + for(;;) { + tag = get_swf_tag(pb, &len); + if (tag < 0) { + fprintf(stderr, "No streaming found in SWF\n"); + return -EIO; + } + if (tag == TAG_STREAMHEAD) { + /* streaming found */ + get_byte(pb); + v = get_byte(pb); + get_le16(pb); + /* if mp3 streaming found, OK */ + if ((v & 0x20) != 0) { + st = av_mallocz(sizeof(AVStream)); + if (!st) + return -ENOMEM; + if (v & 0x01) + st->codec.channels = 2; + else + st->codec.channels = 1; + s->nb_streams = 1; + s->streams[0] = st; + + switch((v>> 2) & 0x03) { + case 1: + st->codec.sample_rate = 11025; + break; + case 2: + st->codec.sample_rate = 22050; + break; + case 3: + st->codec.sample_rate = 44100; + break; + default: + free(st); + return -EIO; + } + st->codec.codec_type = CODEC_TYPE_AUDIO; + st->codec.codec_id = CODEC_ID_MP2; + break; + } + } else { + url_fskip(pb, len); + } + } + + return 0; +} + +static int swf_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + ByteIOContext *pb = &s->pb; + int tag, len; + + for(;;) { + tag = get_swf_tag(pb, &len); + if (tag < 0) + return -EIO; + if (tag == TAG_STREAMBLOCK) { + av_new_packet(pkt, len); + get_buffer(pb, pkt->data, pkt->size); + break; + } else { + url_fskip(pb, len); + } + } + return 0; +} + +static int swf_read_close(AVFormatContext *s) +{ + return 0; +} + +AVFormat swf_format = { + "swf", + "Flash format", + "application/x-shockwave-flash", + "swf", + CODEC_ID_MP2, + CODEC_ID_MJPEG, + swf_write_header, + swf_write_packet, + swf_write_trailer, + + swf_read_header, + swf_read_packet, + swf_read_close, +}; -- cgit v1.2.3