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FFmpeg/libavformat/asf.c
Michael Niedermayer 0888ac4f27 seeking stuff 
adaptively change middle position selection algo for seeking, this avoids some ugly worstcases of the interpolated variant
  avoid backward search for mpeg where possible, its 17 times slower then forward according to my benchmark

Originally committed as revision 2710 to svn://svn.ffmpeg.org/ffmpeg/trunk
2004-01-17 20:26:44 +00:00

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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))
printf("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))
printf("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;
printf("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
printf("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);
printf("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){
printf("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;
}
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