ffmpeg/libavformat/asf.c

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/*
* ASF compatible encoder and decoder.
* Copyright (c) 2000, 2001 Fabrice Bellard.
*
* This library 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 of the License, or (at your option) any later version.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "avformat.h"
#include "avi.h"
#include "mpegaudio.h"
#undef NDEBUG
#include <assert.h>
#define PACKET_SIZE 3200
#define PACKET_HEADER_SIZE 12
#define FRAME_HEADER_SIZE 17
typedef struct {
int num;
int seq;
/* use for reading */
AVPacket pkt;
int frag_offset;
int timestamp;
int64_t duration;
int ds_span; /* descrambling */
int ds_packet_size;
int ds_chunk_size;
int ds_data_size;
int ds_silence_data;
int packet_pos;
} ASFStream;
typedef struct {
uint32_t v1;
uint16_t v2;
uint16_t v3;
uint8_t v4[8];
} GUID;
typedef struct {
GUID guid; // generated by client computer
uint64_t file_size; // in bytes
// invalid if broadcasting
uint64_t create_time; // time of creation, in 100-nanosecond units since 1.1.1601
// invalid if broadcasting
uint64_t packets_count; // how many packets are there in the file
// invalid if broadcasting
uint64_t play_time; // play time, in 100-nanosecond units
// invalid if broadcasting
uint64_t send_time; // time to send file, in 100-nanosecond units
// invalid if broadcasting (could be ignored)
uint32_t preroll; // timestamp of the first packet, in milliseconds
// if nonzero - substract from time
uint32_t ignore; // preroll is 64bit - but let's just ignore it
uint32_t flags; // 0x01 - broadcast
// 0x02 - seekable
// rest is reserved should be 0
uint32_t min_pktsize; // size of a data packet
// invalid if broadcasting
uint32_t max_pktsize; // shall be the same as for min_pktsize
// invalid if broadcasting
uint32_t max_bitrate; // bandwith of stream in bps
// should be the sum of bitrates of the
// individual media streams
} ASFMainHeader;
typedef struct {
int seqno;
int packet_size;
int is_streamed;
int asfid2avid[128]; /* conversion table from asf ID 2 AVStream ID */
ASFStream streams[128]; /* it's max number and it's not that big */
/* non streamed additonnal info */
int64_t nb_packets;
int64_t duration; /* in 100ns units */
/* packet filling */
int packet_size_left;
int packet_timestamp_start;
int packet_timestamp_end;
int packet_nb_frames;
uint8_t packet_buf[PACKET_SIZE];
ByteIOContext pb;
/* only for reading */
uint64_t data_offset; /* begining of the first data packet */
ASFMainHeader hdr;
int packet_flags;
int packet_property;
int packet_timestamp;
int packet_segsizetype;
int packet_segments;
int packet_seq;
int packet_replic_size;
int packet_key_frame;
int packet_padsize;
int packet_frag_offset;
int packet_frag_size;
int packet_frag_timestamp;
int packet_multi_size;
int packet_obj_size;
int packet_time_delta;
int packet_time_start;
int packet_pos;
int stream_index;
ASFStream* asf_st; /* currently decoded stream */
} ASFContext;
static const GUID asf_header = {
0x75B22630, 0x668E, 0x11CF, { 0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C },
};
static const GUID file_header = {
0x8CABDCA1, 0xA947, 0x11CF, { 0x8E, 0xE4, 0x00, 0xC0, 0x0C, 0x20, 0x53, 0x65 },
};
static const GUID stream_header = {
0xB7DC0791, 0xA9B7, 0x11CF, { 0x8E, 0xE6, 0x00, 0xC0, 0x0C, 0x20, 0x53, 0x65 },
};
static const GUID audio_stream = {
0xF8699E40, 0x5B4D, 0x11CF, { 0xA8, 0xFD, 0x00, 0x80, 0x5F, 0x5C, 0x44, 0x2B },
};
static const GUID audio_conceal_none = {
// 0x49f1a440, 0x4ece, 0x11d0, { 0xa3, 0xac, 0x00, 0xa0, 0xc9, 0x03, 0x48, 0xf6 },
// New value lifted from avifile
0x20fb5700, 0x5b55, 0x11cf, { 0xa8, 0xfd, 0x00, 0x80, 0x5f, 0x5c, 0x44, 0x2b },
};
static const GUID video_stream = {
0xBC19EFC0, 0x5B4D, 0x11CF, { 0xA8, 0xFD, 0x00, 0x80, 0x5F, 0x5C, 0x44, 0x2B },
};
static const GUID video_conceal_none = {
0x20FB5700, 0x5B55, 0x11CF, { 0xA8, 0xFD, 0x00, 0x80, 0x5F, 0x5C, 0x44, 0x2B },
};
static const GUID comment_header = {
0x75b22633, 0x668e, 0x11cf, { 0xa6, 0xd9, 0x00, 0xaa, 0x00, 0x62, 0xce, 0x6c },
};
static const GUID codec_comment_header = {
0x86D15240, 0x311D, 0x11D0, { 0xA3, 0xA4, 0x00, 0xA0, 0xC9, 0x03, 0x48, 0xF6 },
};
static const GUID codec_comment1_header = {
0x86d15241, 0x311d, 0x11d0, { 0xa3, 0xa4, 0x00, 0xa0, 0xc9, 0x03, 0x48, 0xf6 },
};
static const GUID data_header = {
0x75b22636, 0x668e, 0x11cf, { 0xa6, 0xd9, 0x00, 0xaa, 0x00, 0x62, 0xce, 0x6c },
};
static const GUID index_guid = {
0x33000890, 0xe5b1, 0x11cf, { 0x89, 0xf4, 0x00, 0xa0, 0xc9, 0x03, 0x49, 0xcb },
};
static const GUID head1_guid = {
0x5fbf03b5, 0xa92e, 0x11cf, { 0x8e, 0xe3, 0x00, 0xc0, 0x0c, 0x20, 0x53, 0x65 },
};
static const GUID head2_guid = {
0xabd3d211, 0xa9ba, 0x11cf, { 0x8e, 0xe6, 0x00, 0xc0, 0x0c, 0x20, 0x53, 0x65 },
};
static const GUID extended_content_header = {
0xD2D0A440, 0xE307, 0x11D2, { 0x97, 0xF0, 0x00, 0xA0, 0xC9, 0x5E, 0xA8, 0x50 },
};
/* I am not a number !!! This GUID is the one found on the PC used to
generate the stream */
static const GUID my_guid = {
0, 0, 0, { 0, 0, 0, 0, 0, 0, 0, 0 },
};
#ifdef CONFIG_ENCODERS
static void put_guid(ByteIOContext *s, const GUID *g)
{
int i;
put_le32(s, g->v1);
put_le16(s, g->v2);
put_le16(s, g->v3);
for(i=0;i<8;i++)
put_byte(s, g->v4[i]);
}
static void put_str16(ByteIOContext *s, const char *tag)
{
int c;
put_le16(s,strlen(tag) + 1);
for(;;) {
c = (uint8_t)*tag++;
put_le16(s, c);
if (c == '\0')
break;
}
}
static void put_str16_nolen(ByteIOContext *s, const char *tag)
{
int c;
for(;;) {
c = (uint8_t)*tag++;
put_le16(s, c);
if (c == '\0')
break;
}
}
static int64_t put_header(ByteIOContext *pb, const GUID *g)
{
int64_t pos;
pos = url_ftell(pb);
put_guid(pb, g);
put_le64(pb, 24);
return pos;
}
/* update header size */
static void end_header(ByteIOContext *pb, int64_t pos)
{
int64_t pos1;
pos1 = url_ftell(pb);
url_fseek(pb, pos + 16, SEEK_SET);
put_le64(pb, pos1 - pos);
url_fseek(pb, pos1, SEEK_SET);
}
/* write an asf chunk (only used in streaming case) */
static void put_chunk(AVFormatContext *s, int type, int payload_length, int flags)
{
ASFContext *asf = s->priv_data;
ByteIOContext *pb = &s->pb;
int length;
length = payload_length + 8;
put_le16(pb, type);
put_le16(pb, length);
put_le32(pb, asf->seqno);
put_le16(pb, flags); /* unknown bytes */
put_le16(pb, length);
asf->seqno++;
}
/* convert from unix to windows time */
static int64_t unix_to_file_time(int ti)
{
int64_t t;
t = ti * int64_t_C(10000000);
t += int64_t_C(116444736000000000);
return t;
}
/* write the header (used two times if non streamed) */
static int asf_write_header1(AVFormatContext *s, int64_t file_size, int64_t data_chunk_size)
{
ASFContext *asf = s->priv_data;
ByteIOContext *pb = &s->pb;
int header_size, n, extra_size, extra_size2, wav_extra_size, file_time;
int has_title;
AVCodecContext *enc;
int64_t header_offset, cur_pos, hpos;
int bit_rate;
has_title = (s->title[0] || s->author[0] || s->copyright[0] || s->comment[0]);
bit_rate = 0;
for(n=0;n<s->nb_streams;n++) {
enc = &s->streams[n]->codec;
bit_rate += enc->bit_rate;
}
if (asf->is_streamed) {
put_chunk(s, 0x4824, 0, 0xc00); /* start of stream (length will be patched later) */
}
put_guid(pb, &asf_header);
put_le64(pb, -1); /* header length, will be patched after */
put_le32(pb, 3 + has_title + s->nb_streams); /* number of chunks in header */
put_byte(pb, 1); /* ??? */
put_byte(pb, 2); /* ??? */
/* file header */
header_offset = url_ftell(pb);
hpos = put_header(pb, &file_header);
put_guid(pb, &my_guid);
put_le64(pb, file_size);
file_time = 0;
put_le64(pb, unix_to_file_time(file_time));
put_le64(pb, asf->nb_packets); /* number of packets */
put_le64(pb, asf->duration); /* end time stamp (in 100ns units) */
put_le64(pb, asf->duration); /* duration (in 100ns units) */
put_le32(pb, 0); /* start time stamp */
put_le32(pb, 0); /* ??? */
put_le32(pb, asf->is_streamed ? 1 : 0); /* ??? */
put_le32(pb, asf->packet_size); /* packet size */
put_le32(pb, asf->packet_size); /* packet size */
put_le32(pb, bit_rate); /* Nominal data rate in bps */
end_header(pb, hpos);
/* unknown headers */
hpos = put_header(pb, &head1_guid);
put_guid(pb, &head2_guid);
put_le32(pb, 6);
put_le16(pb, 0);
end_header(pb, hpos);
/* title and other infos */
if (has_title) {
hpos = put_header(pb, &comment_header);
put_le16(pb, 2 * (strlen(s->title) + 1));
put_le16(pb, 2 * (strlen(s->author) + 1));
put_le16(pb, 2 * (strlen(s->copyright) + 1));
put_le16(pb, 2 * (strlen(s->comment) + 1));
put_le16(pb, 0);
put_str16_nolen(pb, s->title);
put_str16_nolen(pb, s->author);
put_str16_nolen(pb, s->copyright);
put_str16_nolen(pb, s->comment);
end_header(pb, hpos);
}
/* stream headers */
for(n=0;n<s->nb_streams;n++) {
int64_t es_pos;
// ASFStream *stream = &asf->streams[n];
enc = &s->streams[n]->codec;
asf->streams[n].num = n + 1;
asf->streams[n].seq = 0;
switch(enc->codec_type) {
case CODEC_TYPE_AUDIO:
wav_extra_size = 0;
extra_size = 18 + wav_extra_size;
extra_size2 = 0;
break;
default:
case CODEC_TYPE_VIDEO:
wav_extra_size = 0;
extra_size = 0x33;
extra_size2 = 0;
break;
}
hpos = put_header(pb, &stream_header);
if (enc->codec_type == CODEC_TYPE_AUDIO) {
put_guid(pb, &audio_stream);
put_guid(pb, &audio_conceal_none);
} else {
put_guid(pb, &video_stream);
put_guid(pb, &video_conceal_none);
}
put_le64(pb, 0); /* ??? */
es_pos = url_ftell(pb);
put_le32(pb, extra_size); /* wav header len */
put_le32(pb, extra_size2); /* additional data len */
put_le16(pb, n + 1); /* stream number */
put_le32(pb, 0); /* ??? */
if (enc->codec_type == CODEC_TYPE_AUDIO) {
/* WAVEFORMATEX header */
int wavsize = put_wav_header(pb, enc);
if (wavsize < 0)
return -1;
if (wavsize != extra_size) {
cur_pos = url_ftell(pb);
url_fseek(pb, es_pos, SEEK_SET);
put_le32(pb, wavsize); /* wav header len */
url_fseek(pb, cur_pos, SEEK_SET);
}
} else {
put_le32(pb, enc->width);
put_le32(pb, enc->height);
put_byte(pb, 2); /* ??? */
put_le16(pb, 40); /* size */
/* BITMAPINFOHEADER header */
put_bmp_header(pb, enc, codec_bmp_tags, 1);
}
end_header(pb, hpos);
}
/* media comments */
hpos = put_header(pb, &codec_comment_header);
put_guid(pb, &codec_comment1_header);
put_le32(pb, s->nb_streams);
for(n=0;n<s->nb_streams;n++) {
AVCodec *p;
enc = &s->streams[n]->codec;
p = avcodec_find_encoder(enc->codec_id);
put_le16(pb, asf->streams[n].num);
put_str16(pb, p ? p->name : enc->codec_name);
put_le16(pb, 0); /* no parameters */
/* id */
if (enc->codec_type == CODEC_TYPE_AUDIO) {
put_le16(pb, 2);
if(!enc->codec_tag)
enc->codec_tag = codec_get_tag(codec_wav_tags, enc->codec_id);
if(!enc->codec_tag)
return -1;
put_le16(pb, enc->codec_tag);
} else {
put_le16(pb, 4);
if(!enc->codec_tag)
enc->codec_tag = codec_get_tag(codec_bmp_tags, enc->codec_id);
if(!enc->codec_tag)
return -1;
put_le32(pb, enc->codec_tag);
}
}
end_header(pb, hpos);
/* patch the header size fields */
cur_pos = url_ftell(pb);
header_size = cur_pos - header_offset;
if (asf->is_streamed) {
header_size += 8 + 30 + 50;
url_fseek(pb, header_offset - 10 - 30, SEEK_SET);
put_le16(pb, header_size);
url_fseek(pb, header_offset - 2 - 30, SEEK_SET);
put_le16(pb, header_size);
header_size -= 8 + 30 + 50;
}
header_size += 24 + 6;
url_fseek(pb, header_offset - 14, SEEK_SET);
put_le64(pb, header_size);
url_fseek(pb, cur_pos, SEEK_SET);
/* movie chunk, followed by packets of packet_size */
asf->data_offset = cur_pos;
put_guid(pb, &data_header);
put_le64(pb, data_chunk_size);
put_guid(pb, &my_guid);
put_le64(pb, asf->nb_packets); /* nb packets */
put_byte(pb, 1); /* ??? */
put_byte(pb, 1); /* ??? */
return 0;
}
static int asf_write_header(AVFormatContext *s)
{
ASFContext *asf = s->priv_data;
av_set_pts_info(s, 32, 1, 1000); /* 32 bit pts in ms */
asf->packet_size = PACKET_SIZE;
asf->nb_packets = 0;
if (asf_write_header1(s, 0, 50) < 0) {
//av_free(asf);
return -1;
}
put_flush_packet(&s->pb);
asf->packet_nb_frames = 0;
asf->packet_timestamp_start = -1;
asf->packet_timestamp_end = -1;
asf->packet_size_left = asf->packet_size - PACKET_HEADER_SIZE;
init_put_byte(&asf->pb, asf->packet_buf, asf->packet_size, 1,
NULL, NULL, NULL, NULL);
return 0;
}
static int asf_write_stream_header(AVFormatContext *s)
{
ASFContext *asf = s->priv_data;
asf->is_streamed = 1;
return asf_write_header(s);
}
/* write a fixed size packet */
static int put_packet(AVFormatContext *s,
unsigned int timestamp, unsigned int duration,
int nb_frames, int padsize)
{
ASFContext *asf = s->priv_data;
ByteIOContext *pb = &s->pb;
int flags;
if (asf->is_streamed) {
put_chunk(s, 0x4424, asf->packet_size, 0);
}
put_byte(pb, 0x82);
put_le16(pb, 0);
flags = 0x01; /* nb segments present */
if (padsize > 0) {
if (padsize < 256)
flags |= 0x08;
else
flags |= 0x10;
}
put_byte(pb, flags); /* flags */
put_byte(pb, 0x5d);
if (flags & 0x10)
put_le16(pb, padsize - 2);
if (flags & 0x08)
put_byte(pb, padsize - 1);
put_le32(pb, timestamp);
put_le16(pb, duration);
put_byte(pb, nb_frames | 0x80);
return PACKET_HEADER_SIZE + ((flags & 0x18) >> 3);
}
static void flush_packet(AVFormatContext *s)
{
ASFContext *asf = s->priv_data;
int hdr_size, ptr;
hdr_size = put_packet(s, asf->packet_timestamp_start,
asf->packet_timestamp_end - asf->packet_timestamp_start,
asf->packet_nb_frames, asf->packet_size_left);
/* Clear out the padding bytes */
ptr = asf->packet_size - hdr_size - asf->packet_size_left;
memset(asf->packet_buf + ptr, 0, asf->packet_size_left);
put_buffer(&s->pb, asf->packet_buf, asf->packet_size - hdr_size);
put_flush_packet(&s->pb);
asf->nb_packets++;
asf->packet_nb_frames = 0;
asf->packet_timestamp_start = -1;
asf->packet_timestamp_end = -1;
asf->packet_size_left = asf->packet_size - PACKET_HEADER_SIZE;
init_put_byte(&asf->pb, asf->packet_buf, asf->packet_size, 1,
NULL, NULL, NULL, NULL);
}
static void put_frame_header(AVFormatContext *s, ASFStream *stream, int timestamp,
int payload_size, int frag_offset, int frag_len)
{
ASFContext *asf = s->priv_data;
ByteIOContext *pb = &asf->pb;
int val;
val = stream->num;
if (s->streams[val - 1]->codec.coded_frame->key_frame /* && frag_offset == 0 */)
val |= 0x80;
put_byte(pb, val);
put_byte(pb, stream->seq);
put_le32(pb, frag_offset); /* fragment offset */
put_byte(pb, 0x08); /* flags */
put_le32(pb, payload_size);
put_le32(pb, timestamp);
put_le16(pb, frag_len);
}
/* Output a frame. We suppose that payload_size <= PACKET_SIZE.
It is there that you understand that the ASF format is really
crap. They have misread the MPEG Systems spec !
*/
static void put_frame(AVFormatContext *s, ASFStream *stream, int timestamp,
const uint8_t *buf, int payload_size)
{
ASFContext *asf = s->priv_data;
int frag_pos, frag_len, frag_len1;
frag_pos = 0;
while (frag_pos < payload_size) {
frag_len = payload_size - frag_pos;
frag_len1 = asf->packet_size_left - FRAME_HEADER_SIZE;
if (frag_len1 > 0) {
if (frag_len > frag_len1)
frag_len = frag_len1;
put_frame_header(s, stream, timestamp+1, payload_size, frag_pos, frag_len);
put_buffer(&asf->pb, buf, frag_len);
asf->packet_size_left -= (frag_len + FRAME_HEADER_SIZE);
asf->packet_timestamp_end = timestamp;
if (asf->packet_timestamp_start == -1)
asf->packet_timestamp_start = timestamp;
asf->packet_nb_frames++;
} else {
frag_len = 0;
}
frag_pos += frag_len;
buf += frag_len;
/* output the frame if filled */
if (asf->packet_size_left <= FRAME_HEADER_SIZE)
flush_packet(s);
}
stream->seq++;
}
static int asf_write_packet(AVFormatContext *s, int stream_index,
const uint8_t *buf, int size, int64_t timestamp)
{
ASFContext *asf = s->priv_data;
ASFStream *stream;
int64_t duration;
AVCodecContext *codec;
codec = &s->streams[stream_index]->codec;
stream = &asf->streams[stream_index];
if (codec->codec_type == CODEC_TYPE_AUDIO) {
duration = (codec->frame_number * codec->frame_size * int64_t_C(10000000)) /
codec->sample_rate;
} else {
duration = av_rescale(codec->frame_number * codec->frame_rate_base, 10000000, codec->frame_rate);
}
if (duration > asf->duration)
asf->duration = duration;
put_frame(s, stream, timestamp, buf, size);
return 0;
}
static int asf_write_trailer(AVFormatContext *s)
{
ASFContext *asf = s->priv_data;
int64_t file_size;
/* flush the current packet */
if (asf->pb.buf_ptr > asf->pb.buffer)
flush_packet(s);
if (asf->is_streamed) {
put_chunk(s, 0x4524, 0, 0); /* end of stream */
} else {
/* rewrite an updated header */
file_size = url_ftell(&s->pb);
url_fseek(&s->pb, 0, SEEK_SET);
asf_write_header1(s, file_size, file_size - asf->data_offset);
}
put_flush_packet(&s->pb);
return 0;
}
#endif //CONFIG_ENCODERS
/**********************************/
/* decoding */
//#define DEBUG
#ifdef DEBUG
#define PRINT_IF_GUID(g,cmp) \
if (!memcmp(g, &cmp, sizeof(GUID))) \
printf("(GUID: %s) ", #cmp)
static void print_guid(const GUID *g)
{
int i;
PRINT_IF_GUID(g, asf_header);
else PRINT_IF_GUID(g, file_header);
else PRINT_IF_GUID(g, stream_header);
else PRINT_IF_GUID(g, audio_stream);
else PRINT_IF_GUID(g, audio_conceal_none);
else PRINT_IF_GUID(g, video_stream);
else PRINT_IF_GUID(g, video_conceal_none);
else PRINT_IF_GUID(g, comment_header);
else PRINT_IF_GUID(g, codec_comment_header);
else PRINT_IF_GUID(g, codec_comment1_header);
else PRINT_IF_GUID(g, data_header);
else PRINT_IF_GUID(g, index_guid);
else PRINT_IF_GUID(g, head1_guid);
else PRINT_IF_GUID(g, head2_guid);
else PRINT_IF_GUID(g, my_guid);
else
printf("(GUID: unknown) ");
printf("0x%08x, 0x%04x, 0x%04x, {", g->v1, g->v2, g->v3);
for(i=0;i<8;i++)
printf(" 0x%02x,", g->v4[i]);
printf("}\n");
}
#undef PRINT_IF_GUID(g,cmp)
#endif
static void get_guid(ByteIOContext *s, GUID *g)
{
int i;
g->v1 = get_le32(s);
g->v2 = get_le16(s);
g->v3 = get_le16(s);
for(i=0;i<8;i++)
g->v4[i] = get_byte(s);
}
#if 0
static void get_str16(ByteIOContext *pb, char *buf, int buf_size)
{
int len, c;
char *q;
len = get_le16(pb);
q = buf;
while (len > 0) {
c = get_le16(pb);
if ((q - buf) < buf_size - 1)
*q++ = c;
len--;
}
*q = '\0';
}
#endif
static void get_str16_nolen(ByteIOContext *pb, int len, char *buf, int buf_size)
{
int c;
char *q;
q = buf;
while (len > 0) {
c = get_le16(pb);
if ((q - buf) < buf_size - 1)
*q++ = c;
len-=2;
}
*q = '\0';
}
static int asf_probe(AVProbeData *pd)
{
GUID g;
const unsigned char *p;
int i;
/* check file header */
if (pd->buf_size <= 32)
return 0;
p = pd->buf;
g.v1 = p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
p += 4;
g.v2 = p[0] | (p[1] << 8);
p += 2;
g.v3 = p[0] | (p[1] << 8);
p += 2;
for(i=0;i<8;i++)
g.v4[i] = *p++;
if (!memcmp(&g, &asf_header, sizeof(GUID)))
return AVPROBE_SCORE_MAX;
else
return 0;
}
static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
ASFContext *asf = s->priv_data;
GUID g;
ByteIOContext *pb = &s->pb;
AVStream *st;
ASFStream *asf_st;
int size, i;
int64_t gsize;
av_set_pts_info(s, 32, 1, 1000); /* 32 bit pts in ms */
get_guid(pb, &g);
if (memcmp(&g, &asf_header, sizeof(GUID)))
goto fail;
get_le64(pb);
get_le32(pb);
get_byte(pb);
get_byte(pb);
memset(&asf->asfid2avid, -1, sizeof(asf->asfid2avid));
for(;;) {
get_guid(pb, &g);
gsize = get_le64(pb);
#ifdef DEBUG
printf("%08Lx: ", url_ftell(pb) - 24);
print_guid(&g);
printf(" size=0x%Lx\n", gsize);
#endif
if (gsize < 24)
goto fail;
if (!memcmp(&g, &file_header, sizeof(GUID))) {
get_guid(pb, &asf->hdr.guid);
asf->hdr.file_size = get_le64(pb);
asf->hdr.create_time = get_le64(pb);
asf->hdr.packets_count = get_le64(pb);
asf->hdr.play_time = get_le64(pb);
asf->hdr.send_time = get_le64(pb);
asf->hdr.preroll = get_le32(pb);
asf->hdr.ignore = get_le32(pb);
asf->hdr.flags = get_le32(pb);
asf->hdr.min_pktsize = get_le32(pb);
asf->hdr.max_pktsize = get_le32(pb);
asf->hdr.max_bitrate = get_le32(pb);
asf->packet_size = asf->hdr.max_pktsize;
asf->nb_packets = asf->hdr.packets_count;
} else if (!memcmp(&g, &stream_header, sizeof(GUID))) {
int type, total_size, type_specific_size;
unsigned int tag1;
int64_t pos1, pos2;
pos1 = url_ftell(pb);
st = av_new_stream(s, 0);
if (!st)
goto fail;
asf_st = av_mallocz(sizeof(ASFStream));
if (!asf_st)
goto fail;
st->priv_data = asf_st;
st->start_time = asf->hdr.preroll / (10000000 / AV_TIME_BASE);
st->duration = (asf->hdr.send_time - asf->hdr.preroll) /
(10000000 / AV_TIME_BASE);
get_guid(pb, &g);
if (!memcmp(&g, &audio_stream, sizeof(GUID))) {
type = CODEC_TYPE_AUDIO;
} else if (!memcmp(&g, &video_stream, sizeof(GUID))) {
type = CODEC_TYPE_VIDEO;
} else {
goto fail;
}
get_guid(pb, &g);
total_size = get_le64(pb);
type_specific_size = get_le32(pb);
get_le32(pb);
st->id = get_le16(pb) & 0x7f; /* stream id */
// mapping of asf ID to AV stream ID;
asf->asfid2avid[st->id] = s->nb_streams - 1;
get_le32(pb);
st->codec.codec_type = type;
/* 1 fps default (XXX: put 0 fps instead) */
st->codec.frame_rate = 1;
st->codec.frame_rate_base = 1;
if (type == CODEC_TYPE_AUDIO) {
get_wav_header(pb, &st->codec, type_specific_size);
st->need_parsing = 1;
/* We have to init the frame size at some point .... */
pos2 = url_ftell(pb);
if (gsize > (pos2 + 8 - pos1 + 24)) {
asf_st->ds_span = get_byte(pb);
asf_st->ds_packet_size = get_le16(pb);
asf_st->ds_chunk_size = get_le16(pb);
asf_st->ds_data_size = get_le16(pb);
asf_st->ds_silence_data = get_byte(pb);
}
//printf("Descrambling: ps:%d cs:%d ds:%d s:%d sd:%d\n",
// asf_st->ds_packet_size, asf_st->ds_chunk_size,
// asf_st->ds_data_size, asf_st->ds_span, asf_st->ds_silence_data);
if (asf_st->ds_span > 1) {
if (!asf_st->ds_chunk_size
|| (asf_st->ds_packet_size/asf_st->ds_chunk_size <= 1))
asf_st->ds_span = 0; // disable descrambling
}
switch (st->codec.codec_id) {
case CODEC_ID_MP3:
st->codec.frame_size = MPA_FRAME_SIZE;
break;
case CODEC_ID_PCM_S16LE:
case CODEC_ID_PCM_S16BE:
case CODEC_ID_PCM_U16LE:
case CODEC_ID_PCM_U16BE:
case CODEC_ID_PCM_S8:
case CODEC_ID_PCM_U8:
case CODEC_ID_PCM_ALAW:
case CODEC_ID_PCM_MULAW:
st->codec.frame_size = 1;
break;
default:
/* This is probably wrong, but it prevents a crash later */
st->codec.frame_size = 1;
break;
}
} else {
get_le32(pb);
get_le32(pb);
get_byte(pb);
size = get_le16(pb); /* size */
get_le32(pb); /* size */
st->codec.width = get_le32(pb);
st->codec.height = get_le32(pb);
/* not available for asf */
get_le16(pb); /* panes */
st->codec.bits_per_sample = get_le16(pb); /* depth */
tag1 = get_le32(pb);
url_fskip(pb, 20);
if (size > 40) {
st->codec.extradata_size = size - 40;
st->codec.extradata = av_mallocz(st->codec.extradata_size);
get_buffer(pb, st->codec.extradata, st->codec.extradata_size);
}
/* Extract palette from extradata if bpp <= 8 */
/* This code assumes that extradata contains only palette */
/* This is true for all paletted codecs implemented in ffmpeg */
if (st->codec.extradata_size && (st->codec.bits_per_sample <= 8)) {
st->codec.palctrl = av_mallocz(sizeof(AVPaletteControl));
#ifdef WORDS_BIGENDIAN
for (i = 0; i < FFMIN(st->codec.extradata_size, AVPALETTE_SIZE)/4; i++)
st->codec.palctrl->palette[i] = bswap_32(((uint32_t*)st->codec.extradata)[i]);
#else
memcpy(st->codec.palctrl->palette, st->codec.extradata,
FFMIN(st->codec.extradata_size, AVPALETTE_SIZE));
#endif
st->codec.palctrl->palette_changed = 1;
}
st->codec.codec_tag = tag1;
st->codec.codec_id = codec_get_id(codec_bmp_tags, tag1);
}
pos2 = url_ftell(pb);
url_fskip(pb, gsize - (pos2 - pos1 + 24));
} else if (!memcmp(&g, &data_header, sizeof(GUID))) {
break;
} else if (!memcmp(&g, &comment_header, sizeof(GUID))) {
int len1, len2, len3, len4, len5;
len1 = get_le16(pb);
len2 = get_le16(pb);
len3 = get_le16(pb);
len4 = get_le16(pb);
len5 = get_le16(pb);
get_str16_nolen(pb, len1, s->title, sizeof(s->title));
get_str16_nolen(pb, len2, s->author, sizeof(s->author));
get_str16_nolen(pb, len3, s->copyright, sizeof(s->copyright));
get_str16_nolen(pb, len4, s->comment, sizeof(s->comment));
url_fskip(pb, len5);
} else if (!memcmp(&g, &extended_content_header, sizeof(GUID))) {
int desc_count, i;
desc_count = get_le16(pb);
for(i=0;i<desc_count;i++)
{
int name_len,value_type,value_len,value_num = 0;
char *name, *value;
name_len = get_le16(pb);
name = (char *)av_mallocz(name_len);
get_str16_nolen(pb, name_len, name, name_len);
value_type = get_le16(pb);
value_len = get_le16(pb);
if ((value_type == 0) || (value_type == 1)) // unicode or byte
{
value = (char *)av_mallocz(value_len);
get_str16_nolen(pb, value_len, value, value_len);
if (strcmp(name,"WM/AlbumTitle")==0) { strcpy(s->album, value); }
av_free(value);
}
if ((value_type >= 2) || (value_type <= 5)) // boolean or DWORD or QWORD or WORD
{
if (value_type==2) value_num = get_le32(pb);
if (value_type==3) value_num = get_le32(pb);
if (value_type==4) value_num = get_le64(pb);
if (value_type==5) value_num = get_le16(pb);
if (strcmp(name,"WM/Track")==0) s->track = value_num + 1;
if (strcmp(name,"WM/TrackNumber")==0) s->track = value_num;
}
av_free(name);
}
#if 0
} else if (!memcmp(&g, &head1_guid, sizeof(GUID))) {
int v1, v2;
get_guid(pb, &g);
v1 = get_le32(pb);
v2 = get_le16(pb);
} else if (!memcmp(&g, &codec_comment_header, sizeof(GUID))) {
int len, v1, n, num;
char str[256], *q;
char tag[16];
get_guid(pb, &g);
print_guid(&g);
n = get_le32(pb);
for(i=0;i<n;i++) {
num = get_le16(pb); /* stream number */
get_str16(pb, str, sizeof(str));
get_str16(pb, str, sizeof(str));
len = get_le16(pb);
q = tag;
while (len > 0) {
v1 = get_byte(pb);
if ((q - tag) < sizeof(tag) - 1)
*q++ = v1;
len--;
}
*q = '\0';
}
#endif
} else if (url_feof(pb)) {
goto fail;
} else {
url_fseek(pb, gsize - 24, SEEK_CUR);
}
}
get_guid(pb, &g);
get_le64(pb);
get_byte(pb);
get_byte(pb);
if (url_feof(pb))
goto fail;
asf->data_offset = url_ftell(pb);
asf->packet_size_left = 0;
return 0;
fail:
for(i=0;i<s->nb_streams;i++) {
AVStream *st = s->streams[i];
if (st) {
av_free(st->priv_data);
av_free(st->codec.extradata);
}
av_free(st);
}
return -1;
}
#define DO_2BITS(bits, var, defval) \
switch (bits & 3) \
{ \
case 3: var = get_le32(pb); rsize += 4; break; \
case 2: var = get_le16(pb); rsize += 2; break; \
case 1: var = get_byte(pb); rsize++; break; \
default: var = defval; break; \
}
static int asf_get_packet(AVFormatContext *s)
{
ASFContext *asf = s->priv_data;
ByteIOContext *pb = &s->pb;
uint32_t packet_length, padsize;
int rsize = 9;
int c;
assert((url_ftell(&s->pb) - s->data_offset) % asf->packet_size == 0);
c = get_byte(pb);
if (c != 0x82) {
if (!url_feof(pb))
av_log(s, AV_LOG_ERROR, "ff asf bad header %x at:%lld\n", c, url_ftell(pb));
}
if ((c & 0x0f) == 2) { // always true for now
if (get_le16(pb) != 0) {
if (!url_feof(pb))
av_log(s, AV_LOG_ERROR, "ff asf bad non zero\n");
return -EIO;
}
rsize+=2;
/* }else{
if (!url_feof(pb))
printf("ff asf bad header %x at:%lld\n", c, url_ftell(pb));
return -EIO;*/
}
asf->packet_flags = get_byte(pb);
asf->packet_property = get_byte(pb);
DO_2BITS(asf->packet_flags >> 5, packet_length, asf->packet_size);
DO_2BITS(asf->packet_flags >> 1, padsize, 0); // sequence ignored
DO_2BITS(asf->packet_flags >> 3, padsize, 0); // padding length
asf->packet_timestamp = get_le32(pb);
get_le16(pb); /* duration */
// rsize has at least 11 bytes which have to be present
if (asf->packet_flags & 0x01) {
asf->packet_segsizetype = get_byte(pb); rsize++;
asf->packet_segments = asf->packet_segsizetype & 0x3f;
} else {
asf->packet_segments = 1;
asf->packet_segsizetype = 0x80;
}
asf->packet_size_left = packet_length - padsize - rsize;
if (packet_length < asf->hdr.min_pktsize)
padsize += asf->hdr.min_pktsize - packet_length;
asf->packet_padsize = padsize;
#ifdef DEBUG
printf("packet: size=%d padsize=%d left=%d\n", asf->packet_size, asf->packet_padsize, asf->packet_size_left);
#endif
return 0;
}
static int asf_read_packet(AVFormatContext *s, AVPacket *pkt)
{
ASFContext *asf = s->priv_data;
ASFStream *asf_st = 0;
ByteIOContext *pb = &s->pb;
//static int pc = 0;
for (;;) {
int rsize = 0;
if (asf->packet_size_left < FRAME_HEADER_SIZE
|| asf->packet_segments < 1) {
//asf->packet_size_left <= asf->packet_padsize) {
int ret = asf->packet_size_left + asf->packet_padsize;
//printf("PacketLeftSize:%d Pad:%d Pos:%Ld\n", asf->packet_size_left, asf->packet_padsize, url_ftell(pb));
/* fail safe */
url_fskip(pb, ret);
asf->packet_pos= url_ftell(&s->pb);
ret = asf_get_packet(s);
//printf("READ ASF PACKET %d r:%d c:%d\n", ret, asf->packet_size_left, pc++);
if (ret < 0 || url_feof(pb))
return -EIO;
asf->packet_time_start = 0;
continue;
}
if (asf->packet_time_start == 0) {
/* read frame header */
int num = get_byte(pb);
asf->packet_segments--;
rsize++;
asf->packet_key_frame = (num & 0x80) >> 7;
asf->stream_index = asf->asfid2avid[num & 0x7f];
// sequence should be ignored!
DO_2BITS(asf->packet_property >> 4, asf->packet_seq, 0);
DO_2BITS(asf->packet_property >> 2, asf->packet_frag_offset, 0);
DO_2BITS(asf->packet_property, asf->packet_replic_size, 0);
//printf("key:%d stream:%d seq:%d offset:%d replic_size:%d\n", asf->packet_key_frame, asf->stream_index, asf->packet_seq, //asf->packet_frag_offset, asf->packet_replic_size);
if (asf->packet_replic_size > 1) {
assert(asf->packet_replic_size >= 8);
// it should be always at least 8 bytes - FIXME validate
asf->packet_obj_size = get_le32(pb);
asf->packet_frag_timestamp = get_le32(pb); // timestamp
if (asf->packet_replic_size > 8)
url_fskip(pb, asf->packet_replic_size - 8);
rsize += asf->packet_replic_size; // FIXME - check validity
} else if (asf->packet_replic_size==1){
// multipacket - frag_offset is begining timestamp
asf->packet_time_start = asf->packet_frag_offset;
asf->packet_frag_offset = 0;
asf->packet_frag_timestamp = asf->packet_timestamp;
asf->packet_time_delta = get_byte(pb);
rsize++;
}else{
assert(asf->packet_replic_size==0);
}
if (asf->packet_flags & 0x01) {
DO_2BITS(asf->packet_segsizetype >> 6, asf->packet_frag_size, 0); // 0 is illegal
#undef DO_2BITS
//printf("Fragsize %d\n", asf->packet_frag_size);
} else {
asf->packet_frag_size = asf->packet_size_left - rsize;
//printf("Using rest %d %d %d\n", asf->packet_frag_size, asf->packet_size_left, rsize);
}
if (asf->packet_replic_size == 1) {
asf->packet_multi_size = asf->packet_frag_size;
if (asf->packet_multi_size > asf->packet_size_left) {
asf->packet_segments = 0;
continue;
}
}
asf->packet_size_left -= rsize;
//printf("___objsize____ %d %d rs:%d\n", asf->packet_obj_size, asf->packet_frag_offset, rsize);
if (asf->stream_index < 0) {
asf->packet_time_start = 0;
/* unhandled packet (should not happen) */
url_fskip(pb, asf->packet_frag_size);
asf->packet_size_left -= asf->packet_frag_size;
av_log(s, AV_LOG_ERROR, "ff asf skip %d %d\n", asf->packet_frag_size, num & 0x7f);
continue;
}
asf->asf_st = s->streams[asf->stream_index]->priv_data;
}
asf_st = asf->asf_st;
if ((asf->packet_frag_offset != asf_st->frag_offset
|| (asf->packet_frag_offset
&& asf->packet_seq != asf_st->seq)) // seq should be ignored
) {
/* cannot continue current packet: free it */
// FIXME better check if packet was already allocated
av_log(s, AV_LOG_INFO, "ff asf parser skips: %d - %d o:%d - %d %d %d fl:%d\n",
asf_st->pkt.size,
asf->packet_obj_size,
asf->packet_frag_offset, asf_st->frag_offset,
asf->packet_seq, asf_st->seq, asf->packet_frag_size);
if (asf_st->pkt.size)
av_free_packet(&asf_st->pkt);
asf_st->frag_offset = 0;
if (asf->packet_frag_offset != 0) {
url_fskip(pb, asf->packet_frag_size);
av_log(s, AV_LOG_INFO, "ff asf parser skiping %db\n", asf->packet_frag_size);
asf->packet_size_left -= asf->packet_frag_size;
continue;
}
}
if (asf->packet_replic_size == 1) {
// frag_offset is here used as the begining timestamp
asf->packet_frag_timestamp = asf->packet_time_start;
asf->packet_time_start += asf->packet_time_delta;
asf->packet_obj_size = asf->packet_frag_size = get_byte(pb);
asf->packet_size_left--;
asf->packet_multi_size--;
if (asf->packet_multi_size < asf->packet_obj_size)
{
asf->packet_time_start = 0;
url_fskip(pb, asf->packet_multi_size);
asf->packet_size_left -= asf->packet_multi_size;
continue;
}
asf->packet_multi_size -= asf->packet_obj_size;
//printf("COMPRESS size %d %d %d ms:%d\n", asf->packet_obj_size, asf->packet_frag_timestamp, asf->packet_size_left, asf->packet_multi_size);
}
if (asf_st->frag_offset == 0) {
/* new packet */
av_new_packet(&asf_st->pkt, asf->packet_obj_size);
asf_st->seq = asf->packet_seq;
asf_st->pkt.pts = asf->packet_frag_timestamp - asf->hdr.preroll;
asf_st->pkt.stream_index = asf->stream_index;
asf_st->packet_pos= asf->packet_pos;
//printf("new packet: stream:%d key:%d packet_key:%d audio:%d size:%d\n",
//asf->stream_index, asf->packet_key_frame, asf_st->pkt.flags & PKT_FLAG_KEY,
//s->streams[asf->stream_index]->codec.codec_type == CODEC_TYPE_AUDIO, asf->packet_obj_size);
if (s->streams[asf->stream_index]->codec.codec_type == CODEC_TYPE_AUDIO)
asf->packet_key_frame = 1;
if (asf->packet_key_frame)
asf_st->pkt.flags |= PKT_FLAG_KEY;
}
/* read data */
//printf("READ PACKET s:%d os:%d o:%d,%d l:%d DATA:%p\n",
// asf->packet_size, asf_st->pkt.size, asf->packet_frag_offset,
// asf_st->frag_offset, asf->packet_frag_size, asf_st->pkt.data);
asf->packet_size_left -= asf->packet_frag_size;
if (asf->packet_size_left < 0)
continue;
get_buffer(pb, asf_st->pkt.data + asf->packet_frag_offset,
asf->packet_frag_size);
asf_st->frag_offset += asf->packet_frag_size;
/* test if whole packet is read */
if (asf_st->frag_offset == asf_st->pkt.size) {
/* return packet */
if (asf_st->ds_span > 1) {
/* packet descrambling */
char* newdata = av_malloc(asf_st->pkt.size);
if (newdata) {
int offset = 0;
while (offset < asf_st->pkt.size) {
int off = offset / asf_st->ds_chunk_size;
int row = off / asf_st->ds_span;
int col = off % asf_st->ds_span;
int idx = row + col * asf_st->ds_packet_size / asf_st->ds_chunk_size;
//printf("off:%d row:%d col:%d idx:%d\n", off, row, col, idx);
memcpy(newdata + offset,
asf_st->pkt.data + idx * asf_st->ds_chunk_size,
asf_st->ds_chunk_size);
offset += asf_st->ds_chunk_size;
}
av_free(asf_st->pkt.data);
asf_st->pkt.data = newdata;
}
}
asf_st->frag_offset = 0;
memcpy(pkt, &asf_st->pkt, sizeof(AVPacket));
//printf("packet %d %d\n", asf_st->pkt.size, asf->packet_frag_size);
asf_st->pkt.size = 0;
asf_st->pkt.data = 0;
break; // packet completed
}
}
return 0;
}
static int asf_read_close(AVFormatContext *s)
{
int i;
for(i=0;i<s->nb_streams;i++) {
AVStream *st = s->streams[i];
av_free(st->priv_data);
av_free(st->codec.extradata);
av_free(st->codec.palctrl);
}
return 0;
}
// Added to support seeking after packets have been read
// If information is not reset, read_packet fails due to
// leftover information from previous reads
static void asf_reset_header(AVFormatContext *s)
{
ASFContext *asf = s->priv_data;
ASFStream *asf_st;
int i;
asf->packet_nb_frames = 0;
asf->packet_timestamp_start = -1;
asf->packet_timestamp_end = -1;
asf->packet_size_left = 0;
asf->packet_segments = 0;
asf->packet_flags = 0;
asf->packet_property = 0;
asf->packet_timestamp = 0;
asf->packet_segsizetype = 0;
asf->packet_segments = 0;
asf->packet_seq = 0;
asf->packet_replic_size = 0;
asf->packet_key_frame = 0;
asf->packet_padsize = 0;
asf->packet_frag_offset = 0;
asf->packet_frag_size = 0;
asf->packet_frag_timestamp = 0;
asf->packet_multi_size = 0;
asf->packet_obj_size = 0;
asf->packet_time_delta = 0;
asf->packet_time_start = 0;
for(i=0; i<s->nb_streams; i++){
asf_st= s->streams[i]->priv_data;
av_free_packet(&asf_st->pkt);
asf_st->frag_offset=0;
asf_st->seq=0;
}
asf->asf_st= NULL;
}
static int64_t asf_read_pts(AVFormatContext *s, int64_t *ppos, int stream_index)
{
ASFContext *asf = s->priv_data;
AVPacket pkt1, *pkt = &pkt1;
ASFStream *asf_st;
int64_t pts;
int64_t pos= *ppos;
int i;
int64_t start_pos[s->nb_streams];
for(i=0; i<s->nb_streams; i++){
start_pos[i]= pos;
}
//printf("asf_read_pts\n");
url_fseek(&s->pb, pos*asf->packet_size + s->data_offset, SEEK_SET);
asf_reset_header(s);
for(;;){
if (av_read_frame(s, pkt) < 0){
av_log(s, AV_LOG_INFO, "seek failed\n");
return AV_NOPTS_VALUE;
}
pts= pkt->pts;
av_free_packet(pkt);
if(pkt->flags&PKT_FLAG_KEY){
i= pkt->stream_index;
asf_st= s->streams[i]->priv_data;
assert((asf_st->packet_pos - s->data_offset) % asf->packet_size == 0);
pos= (asf_st->packet_pos - s->data_offset) / asf->packet_size;
av_add_index_entry(s->streams[i], pos, pts, pos - start_pos[i] + 1, AVINDEX_KEYFRAME);
start_pos[i]= pos + 1;
if(pkt->stream_index == stream_index)
break;
}
}
*ppos= pos;
//printf("found keyframe at %Ld stream %d stamp:%Ld\n", *ppos, stream_index, pts);
return pts;
}
static int asf_read_seek(AVFormatContext *s, int stream_index, int64_t pts)
{
ASFContext *asf = s->priv_data;
AVStream *st;
int64_t pos;
int64_t pos_min, pos_max, pts_min, pts_max, cur_pts, pos_limit;
int no_change;
if (stream_index == -1)
stream_index= av_find_default_stream_index(s);
if (asf->packet_size <= 0)
return -1;
pts_max=
pts_min= AV_NOPTS_VALUE;
pos_max= pos_limit= -1; // gcc thinks its uninitalized
st= s->streams[stream_index];
if(st->index_entries){
AVIndexEntry *e;
int index;
index= av_index_search_timestamp(st, pts);
e= &st->index_entries[index];
if(e->timestamp <= pts){
pos_min= e->pos;
pts_min= e->timestamp;
#ifdef DEBUG_SEEK
printf("unsing cached pos_min=0x%llx dts_min=%0.3f\n",
pos_min,pts_min / 90000.0);
#endif
}else{
assert(index==0);
}
index++;
if(index < st->nb_index_entries){
e= &st->index_entries[index];
assert(e->timestamp >= pts);
pos_max= e->pos;
pts_max= e->timestamp;
pos_limit= pos_max - e->min_distance;
#ifdef DEBUG_SEEK
printf("unsing cached pos_max=0x%llx dts_max=%0.3f\n",
pos_max,pts_max / 90000.0);
#endif
}
}
if(pts_min == AV_NOPTS_VALUE){
pos_min = 0;
pts_min = asf_read_pts(s, &pos_min, stream_index);
if (pts_min == AV_NOPTS_VALUE) return -1;
}
if(pts_max == AV_NOPTS_VALUE){
pos_max = (url_filesize(url_fileno(&s->pb)) - 1 - s->data_offset) / asf->packet_size; //FIXME wrong
pts_max = s->duration; //FIXME wrong
pos_limit= pos_max;
}
no_change=0;
while (pos_min < pos_limit) {
int64_t start_pos;
assert(pos_limit <= pos_max);
if(no_change==0){
int64_t approximate_keyframe_distance= pos_max - pos_limit;
// interpolate position (better than dichotomy)
pos = (int64_t)((double)(pos_max - pos_min) *
(double)(pts - pts_min) /
(double)(pts_max - pts_min)) + pos_min - approximate_keyframe_distance;
}else if(no_change==1){
// bisection, if interpolation failed to change min or max pos last time
pos = (pos_min + pos_limit)>>1;
}else{
// linear search if bisection failed, can only happen if there are very few or no keyframes between min/max
pos=pos_min;
}
if(pos <= pos_min)
pos= pos_min + 1;
else if(pos > pos_limit)
pos= pos_limit;
start_pos= pos;
// read the next timestamp
cur_pts = asf_read_pts(s, &pos, stream_index);
if(pos == pos_max)
no_change++;
else
no_change=0;
#ifdef DEBUG_SEEK
printf("%Ld %Ld %Ld / %Ld %Ld %Ld target:%Ld limit:%Ld start:%Ld\n", pos_min, pos, pos_max, pts_min, cur_pts, pts_max, pts, pos_limit, start_pos);
#endif
assert (cur_pts != AV_NOPTS_VALUE);
if (pts < cur_pts) {
pos_limit = start_pos - 1;
pos_max = pos;
pts_max = cur_pts;
} else {
pos_min = pos;
pts_min = cur_pts;
/* check if we are lucky */
if (pts == cur_pts)
break;
}
}
pos = pos_min;
url_fseek(&s->pb, pos*asf->packet_size + s->data_offset, SEEK_SET);
asf_reset_header(s);
return 0;
}
static AVInputFormat asf_iformat = {
"asf",
"asf format",
sizeof(ASFContext),
asf_probe,
asf_read_header,
asf_read_packet,
asf_read_close,
asf_read_seek,
};
#ifdef CONFIG_ENCODERS
static AVOutputFormat asf_oformat = {
"asf",
"asf format",
"video/x-ms-asf",
"asf,wmv",
sizeof(ASFContext),
#ifdef CONFIG_MP3LAME
CODEC_ID_MP3,
#else
CODEC_ID_MP2,
#endif
CODEC_ID_MSMPEG4V3,
asf_write_header,
asf_write_packet,
asf_write_trailer,
};
static AVOutputFormat asf_stream_oformat = {
"asf_stream",
"asf format",
"video/x-ms-asf",
"asf,wmv",
sizeof(ASFContext),
#ifdef CONFIG_MP3LAME
CODEC_ID_MP3,
#else
CODEC_ID_MP2,
#endif
CODEC_ID_MSMPEG4V3,
asf_write_stream_header,
asf_write_packet,
asf_write_trailer,
};
#endif //CONFIG_ENCODERS
int asf_init(void)
{
av_register_input_format(&asf_iformat);
#ifdef CONFIG_ENCODERS
av_register_output_format(&asf_oformat);
av_register_output_format(&asf_stream_oformat);
#endif //CONFIG_ENCODERS
return 0;
}