FFmpeg/libavformat/nut.c

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/*
* "NUT" Container Format muxer and demuxer (DRAFT-20031003)
* Copyright (c) 2003 Alex Beregszaszi
*
* 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 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
*
* NUT DRAFT can be found in MPlayer CVS at DOCS/tech/mpcf.txt
*
* AND http://people.fsn.hu/~alex/nut/ (TeX, pdf, ps, dvi, ..)
*
*/
/*
* TODO:
* - checksumming
* - optimal timestamp handling
* - index writing
* - info and index packet reading support
* - startcode searching for broken streams
* - subpacket support
*/
//#define DEBUG 1
#include "avformat.h"
#include "mpegaudio.h"
#include "avi.h"
//from /dev/random
#define MAIN_STARTCODE (0xF9526A6200000000ULL + ('N'<<24) + ('U'<<16) + ('T'<<8) + 'M')
#define STREAM_STARTCODE (0xD667773F00000000ULL + ('N'<<24) + ('U'<<16) + ('T'<<8) + 'S')
#define KEYFRAME_STARTCODE (0xCB86308700000000ULL + ('N'<<24) + ('U'<<16) + ('T'<<8) + 'K')
#define INDEX_STARTCODE (0xEBFCDE0E00000000ULL + ('N'<<24) + ('U'<<16) + ('T'<<8) + 'X')
#define INFO_STARTCODE (0xA37B643500000000ULL + ('N'<<24) + ('U'<<16) + ('T'<<8) + 'I')
typedef struct {
int curr_frame_start;
int last_frame_size;
int curr_frame_size;
int *msb_timestamp_shift;
int64_t *last_msb_timestamp;
} NUTContext;
static int bytes_left(ByteIOContext *bc)
{
return bc->buf_end - bc->buf_ptr;
}
static uint64_t get_v(ByteIOContext *bc)
{
uint64_t val = 0;
for(; bytes_left(bc) > 0; )
{
int tmp = get_byte(bc);
if (tmp&0x80)
val= (val<<7) + tmp - 0x80;
else
return (val<<7) + tmp;
}
return -1;
}
static int64_t get_s(ByteIOContext *bc)
{
int64_t v = get_v(bc) + 1;
if (v&1)
return -(v>>1);
else
return (v>>1);
}
static int get_b(ByteIOContext *bc, char *data, int maxlen)
{
int i, len;
len = get_v(bc);
for (i = 0; i < len && i < maxlen; i++)
data[i] = get_byte(bc);
/* skip remaining bytes */
url_fskip(bc, len-i);
return 0;
}
static int get_bi(ByteIOContext *bc)
{
int i, len, val = 0;
len = get_v(bc);
for (i = 0; i < len && i <= 4; i++)
val |= get_byte(bc) << (i * 8);
/* skip remaining bytes */
url_fskip(bc, len-i);
return val;
}
static int get_packetheader(NUTContext *nut, ByteIOContext *bc)
{
nut->curr_frame_start = url_ftell(bc);
nut->curr_frame_size = get_v(bc);
nut->last_frame_size = get_v(bc);
dprintf("Packet: fwd: %d bwd: %d\n",
nut->curr_frame_size, nut->last_frame_size);
return 0;
}
/**
*
*/
static int get_length(uint64_t val){
int i;
for (i=7; ; i+=7)
if ((val>>i) == 0)
return i;
return 7; //not reached
}
#ifdef CONFIG_ENCODERS
static int put_v(ByteIOContext *bc, uint64_t val)
{
int i;
// if (bytes_left(s)*8 < 9)
// return -1;
if (bytes_left(bc) < 1)
return -1;
val &= 0x7FFFFFFFFFFFFFFFULL; // FIXME can only encode upto 63 bits currently
i= get_length(val);
for (i-=7; i>0; i-=7){
put_byte(bc, 0x80 | (val>>i));
}
put_byte(bc, val&0x7f);
return 0;
}
static int put_s(ByteIOContext *bc, uint64_t val)
{
if (val<=0)
return put_v(bc, -2*val);
else
return put_v(bc, 2*val-1);
}
static int put_b(ByteIOContext *bc, char *data, int len)
{
int i;
put_v(bc, len);
for (i = 0; i < len; i++)
put_byte(bc, data[i]);
return 0;
}
static int put_bi(ByteIOContext *bc, int val)
{
put_v(bc, 4);
put_le32(bc, val);
return 0;
}
static int put_packetheader(NUTContext *nut, ByteIOContext *bc, int max_size)
{
put_flush_packet(bc);
nut->curr_frame_start = url_ftell(bc);
nut->curr_frame_size = max_size;
/* packet header */
put_v(bc, nut->curr_frame_size); /* forward ptr */
put_v(bc, nut->last_frame_size); /* backward ptr */
dprintf("Packet: fwd: %d, bwd: %d\n",
nut->curr_frame_size, nut->last_frame_size);
nut->last_frame_size = nut->curr_frame_size;
return 0;
}
static int update_packetheader(NUTContext *nut, ByteIOContext *bc, int additional_size){
offset_t start= nut->curr_frame_start;
offset_t cur= url_ftell(bc);
int size= cur - start + additional_size;
assert( size <= nut->curr_frame_size );
url_fseek(bc, start, SEEK_SET);
put_v(bc, size);
if(get_length(size) < get_length(nut->curr_frame_size))
put_byte(bc, 0x80);
nut->curr_frame_size= size;
dprintf("Packet update: size: %d\n", size);
url_fseek(bc, cur, SEEK_SET);
return 0;
}
static int nut_write_header(AVFormatContext *s)
{
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb;
AVCodecContext *codec;
int i;
/* main header */
put_be64(bc, MAIN_STARTCODE);
put_packetheader(nut, bc, 120);
put_v(bc, 0); /* version */
put_v(bc, s->nb_streams);
put_be32(bc, 0); /* FIXME: checksum */
update_packetheader(nut, bc, 0);
nut->msb_timestamp_shift =
av_mallocz(sizeof(nut->msb_timestamp_shift)*s->nb_streams);
nut->last_msb_timestamp =
av_mallocz(sizeof(nut->last_msb_timestamp)*s->nb_streams);
/* stream headers */
for (i = 0; i < s->nb_streams; i++)
{
int nom, denom;
codec = &s->streams[i]->codec;
put_be64(bc, STREAM_STARTCODE);
put_packetheader(nut, bc, 120);
put_v(bc, i /*s->streams[i]->index*/);
put_v(bc, (codec->codec_type == CODEC_TYPE_AUDIO) ? 32 : 0);
if (codec->codec_tag)
put_bi(bc, codec->codec_tag);
else if (codec->codec_type == CODEC_TYPE_VIDEO)
{
int tmp = codec_get_bmp_tag(codec->codec_id);
put_bi(bc, tmp);
}
else if (codec->codec_type == CODEC_TYPE_AUDIO)
{
int tmp = codec_get_wav_tag(codec->codec_id);
put_bi(bc, tmp);
}
if (codec->codec_type == CODEC_TYPE_VIDEO)
{
nom = codec->frame_rate;
denom = codec->frame_rate_base;
}
else
{
nom = codec->sample_rate/8;
denom = 8;
}
put_v(bc, codec->bit_rate);
put_v(bc, 0); /* no language code */
put_v(bc, nom);
put_v(bc, denom);
nut->msb_timestamp_shift[i] = 0;
put_v(bc, nut->msb_timestamp_shift[i]);
put_v(bc, 0); /* shuffle type */
put_byte(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */
put_v(bc, 0); /* no codec specific headers */
switch(codec->codec_type)
{
case CODEC_TYPE_AUDIO:
put_v(bc, (codec->sample_rate * denom) / nom);
put_v(bc, codec->channels);
put_be32(bc, 0); /* FIXME: checksum */
break;
case CODEC_TYPE_VIDEO:
put_v(bc, codec->width);
put_v(bc, codec->height);
put_v(bc, 0); /* aspected w */
put_v(bc, 0); /* aspected h */
put_v(bc, 0); /* csp type -- unknown */
put_be32(bc, 0); /* FIXME: checksum */
break;
default:
break;
}
update_packetheader(nut, bc, 0);
}
#if 0
/* info header */
put_be64(bc, INFO_STARTCODE);
put_packetheader(nut, bc, 16+strlen(s->author)+strlen(s->title)+
strlen(s->comment)+strlen(s->copyright));
if (s->author[0])
{
put_v(bc, 5); /* type */
put_b(bc, s->author, strlen(s->author));
}
if (s->title[0])
{
put_v(bc, 6); /* type */
put_b(bc, s->title, strlen(s->title));
}
if (s->comment[0])
{
put_v(bc, 7); /* type */
put_b(bc, s->comment, strlen(s->comment));
}
if (s->copyright[0])
{
put_v(bc, 8); /* type */
put_b(bc, s->copyright, strlen(s->copyright));
}
/* encoder */
put_v(bc, 9); /* type */
put_b(bc, LIBAVFORMAT_IDENT "\0", strlen(LIBAVFORMAT_IDENT));
put_v(bc, 0); /* eof info */
put_be32(bc, 0); /* FIXME: checksum */
update_packetheader(nut, bc, 0);
#endif
put_flush_packet(bc);
return 0;
}
static int nut_write_packet(AVFormatContext *s, int stream_index,
const uint8_t *buf, int size, int64_t pts)
{
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb;
int key_frame = 0, flags, msb_pts = 0;
AVCodecContext *enc;
int64_t lsb_pts;
if (stream_index > s->nb_streams)
return 1;
enc = &s->streams[stream_index]->codec;
// FIXME, lavc reports always keyframes for audio, which will make
// _huge_ overhead
if (enc->codec_type == CODEC_TYPE_VIDEO)
key_frame = enc->coded_frame->key_frame;
if (key_frame /*||
((pts - (nut->last_msb_timestamp[stream_index] <<
nut->msb_timestamp_shift[stream_index])) > 1024)*/)
{
msb_pts = 1;
nut->last_msb_timestamp[stream_index] = pts >> nut->msb_timestamp_shift[stream_index];
}
lsb_pts = pts - (nut->last_msb_timestamp[stream_index] << nut->msb_timestamp_shift[stream_index]);
flags=0;
flags<<=2; flags|=1; //priority
flags<<=1; flags|=0; //checksum
flags<<=1; flags|=msb_pts; //msb_timestamp_flag
flags<<=2; flags|=1; //subpacket_type
flags<<=1; flags|=0; //reserved
if (key_frame)
put_be64(bc, KEYFRAME_STARTCODE);
put_byte(bc, flags);
put_packetheader(nut, bc, size+20);
put_v(bc, stream_index);
if (msb_pts)
put_v(bc, nut->last_msb_timestamp[stream_index]);
put_v(bc, lsb_pts); /* lsb_timestamp */
update_packetheader(nut, bc, size);
put_buffer(bc, buf, size);
put_flush_packet(bc);
return 0;
}
static int nut_write_trailer(AVFormatContext *s)
{
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb;
#if 0
int i;
/* WRITE INDEX */
for (i = 0; s->nb_streams; i++)
{
put_be64(bc, INDEX_STARTCODE);
put_packetheader(nut, bc, 64);
put_v(bc, s->streams[i]->id);
put_v(bc, ...);
put_be32(bc, 0); /* FIXME: checksum */
update_packetheader(nut, bc, 0);
}
#endif
put_flush_packet(bc);
if (nut->last_msb_timestamp)
av_free(nut->last_msb_timestamp);
if (nut->msb_timestamp_shift)
av_free(nut->msb_timestamp_shift);
return 0;
}
#endif //CONFIG_ENCODERS
static int nut_probe(AVProbeData *p)
{
int i;
uint64_t code;
code = 0xff;
for (i = 0; i < p->buf_size; i++) {
int c = p->buf[i];
code = (code << 8) | c;
if (code == MAIN_STARTCODE)
return AVPROBE_SCORE_MAX;
}
return 0;
}
static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb;
uint64_t tmp;
int cur_stream, nb_streams;
/* main header */
tmp = get_be64(bc);
if (tmp != MAIN_STARTCODE)
fprintf(stderr, "damaged? startcode!=1 (%Ld)\n", tmp);
get_packetheader(nut, bc);
tmp = get_v(bc);
if (tmp != 0)
fprintf(stderr, "bad version (%Ld)\n", tmp);
nb_streams = get_v(bc);
get_be32(bc); /* checkusm */
s->bit_rate = 0;
nut->msb_timestamp_shift =
av_malloc(sizeof(nut->msb_timestamp_shift)*s->nb_streams);
nut->last_msb_timestamp =
av_malloc(sizeof(nut->last_msb_timestamp)*s->nb_streams);
/* stream header */
for (cur_stream = 0; cur_stream < nb_streams; cur_stream++)
{
int class, nom, denom;
AVStream *st;
tmp = get_be64(bc);
if (tmp != STREAM_STARTCODE)
fprintf(stderr, "damaged? startcode!=1 (%Ld)\n", tmp);
get_packetheader(nut, bc);
st = av_new_stream(s, get_v(bc));
if (!st)
return AVERROR_NOMEM;
class = get_v(bc);
tmp = get_bi(bc);
switch(class)
{
case 0:
st->codec.codec_type = CODEC_TYPE_VIDEO;
st->codec.codec_id = codec_get_bmp_id(tmp);
if (st->codec.codec_id == CODEC_ID_NONE)
fprintf(stderr, "Unknown codec?!\n");
break;
case 32:
st->codec.codec_type = CODEC_TYPE_AUDIO;
st->codec.codec_id = codec_get_wav_id(tmp);
if (st->codec.codec_id == CODEC_ID_NONE)
fprintf(stderr, "Unknown codec?!\n");
break;
default:
fprintf(stderr, "Unknown stream class (%d)\n", class);
return -1;
}
s->bit_rate += get_v(bc);
get_b(bc, NULL, 0); /* language code */
nom = get_v(bc);
denom = get_v(bc);
nut->msb_timestamp_shift[cur_stream] = get_v(bc);
get_v(bc); /* shuffle type */
get_byte(bc); /* flags */
/* codec specific data headers */
while(get_v(bc) != 0)
url_fskip(bc, get_v(bc));
if (class == 0) /* VIDEO */
{
st->codec.width = get_v(bc);
st->codec.height = get_v(bc);
get_v(bc); /* aspected w */
get_v(bc); /* aspected h */
get_v(bc); /* csp type */
get_be32(bc); /* checksum */
st->codec.frame_rate = nom;
st->codec.frame_rate_base = denom;
}
if (class == 32) /* AUDIO */
{
st->codec.sample_rate = (get_v(bc) * nom) / denom;
st->codec.channels = get_v(bc);
get_be32(bc); /* checksum */
}
}
return 0;
}
static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
{
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb;
int id, size;
int key_frame = 0;
uint64_t tmp;
int64_t pts = 0;
if (url_feof(bc))
return -1;
tmp = get_byte(bc);
if (tmp & 0x80) /* zero bit set? */
{
tmp<<=8 ; tmp |= get_byte(bc);
tmp<<=16; tmp |= get_be16(bc);
tmp<<=32; tmp |= get_be32(bc);
if (tmp == KEYFRAME_STARTCODE)
{
key_frame = 1;
tmp = get_byte(bc); /* flags */
}
else
fprintf(stderr, "error in zero bit / startcode %LX\n", tmp);
}
get_packetheader(nut, bc);
#if 0
if (((tmp & 0x60)>>5) > 3) /* priority <= 3 */
fprintf(stderr, "sanity check failed!\n");
#endif
id = get_v(bc);
if ((tmp & 0x8) >> 3)
pts = get_v(bc) << nut->msb_timestamp_shift[id];
pts += get_v(bc);
size = (nut->curr_frame_size - (url_ftell(bc)-nut->curr_frame_start));
dprintf("flags: 0x%llx, timestamp: %llx, packet size: %d\n", tmp, pts, size);
if (size < 0)
return -1;
av_new_packet(pkt, size);
get_buffer(bc, pkt->data, size);
pkt->stream_index = id;
if (key_frame)
pkt->flags |= PKT_FLAG_KEY;
pkt->pts = pts;
return 0;
}
static AVInputFormat nut_iformat = {
"nut",
"nut format",
sizeof(NUTContext),
nut_probe,
nut_read_header,
nut_read_packet,
// nut_read_close,
// nut_read_seek,
.extensions = "nut",
};
#ifdef CONFIG_ENCODERS
static AVOutputFormat nut_oformat = {
"nut",
"nut format",
"video/x-nut",
"nut",
sizeof(NUTContext),
#ifdef CONFIG_VORBIS
CODEC_ID_VORBIS,
#elif defined(CONFIG_MP3LAME)
CODEC_ID_MP3,
#else
CODEC_ID_MP2, /* AC3 needs liba52 decoder */
#endif
CODEC_ID_MPEG4,
nut_write_header,
nut_write_packet,
nut_write_trailer,
};
#endif //CONFIG_ENCODERS
int nut_init(void)
{
av_register_input_format(&nut_iformat);
#ifdef CONFIG_ENCODERS
av_register_output_format(&nut_oformat);
#endif //CONFIG_ENCODERS
return 0;
}