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ffmpeg/libavformat/nut.c

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/*
* "NUT" Container Format muxer and demuxer (DRAFT-200403??)
* Copyright (c) 2003 Alex Beregszaszi
* Copyright (c) 2004 Michael Niedermayer
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*
* Visit the official site at http://www.nut.hu/
*
*/
/*
* TODO:
* - index writing
* - index packet reading support
*/
//#define DEBUG 1
#include <limits.h>
#include "avformat.h"
#include "mpegaudio.h"
#include "riff.h"
#include "adler32.h"
#undef NDEBUG
#include <assert.h>
//#define TRACE
//from /dev/random
#define MAIN_STARTCODE (0x7A561F5F04ADULL + (((uint64_t)('N'<<8) + 'M')<<48))
#define STREAM_STARTCODE (0x11405BF2F9DBULL + (((uint64_t)('N'<<8) + 'S')<<48))
#define KEYFRAME_STARTCODE (0xE4ADEECA4569ULL + (((uint64_t)('N'<<8) + 'K')<<48))
#define INDEX_STARTCODE (0xDD672F23E64EULL + (((uint64_t)('N'<<8) + 'X')<<48))
#define INFO_STARTCODE (0xAB68B596BA78ULL + (((uint64_t)('N'<<8) + 'I')<<48))
#define ID_STRING "nut/multimedia container\0"
#define MAX_DISTANCE (1024*16-1)
#define MAX_SHORT_DISTANCE (1024*4-1)
#define FLAG_DATA_SIZE 1
#define FLAG_KEY_FRAME 2
#define FLAG_INVALID 4
typedef struct {
uint8_t flags;
uint8_t stream_id_plus1;
uint16_t size_mul;
uint16_t size_lsb;
int16_t timestamp_delta;
uint8_t reserved_count;
} FrameCode;
typedef struct {
int last_key_frame;
int msb_timestamp_shift;
int rate_num;
int rate_den;
int64_t last_pts;
int64_t last_sync_pos; ///<pos of last 1/2 type frame
int decode_delay;
} StreamContext;
typedef struct {
AVFormatContext *avf;
int written_packet_size;
int64_t packet_start[3]; //0-> startcode less, 1-> short startcode 2-> long startcodes
FrameCode frame_code[256];
unsigned int stream_count;
uint64_t next_startcode; ///< stores the next startcode if it has alraedy been parsed but the stream isnt seekable
StreamContext *stream;
int max_distance;
int max_short_distance;
int rate_num;
int rate_den;
int short_startcode;
} NUTContext;
static char *info_table[][2]={
{NULL , NULL }, // end
{NULL , NULL },
{NULL , "UTF8"},
{NULL , "v"},
{NULL , "s"},
{"StreamId" , "v"},
{"SegmentId" , "v"},
{"StartTimestamp" , "v"},
{"EndTimestamp" , "v"},
{"Author" , "UTF8"},
{"Title" , "UTF8"},
{"Description" , "UTF8"},
{"Copyright" , "UTF8"},
{"Encoder" , "UTF8"},
{"Keyword" , "UTF8"},
{"Cover" , "JPEG"},
{"Cover" , "PNG"},
};
static void update(NUTContext *nut, int stream_index, int64_t frame_start, int frame_type, int frame_code, int key_frame, int size, int64_t pts){
StreamContext *stream= &nut->stream[stream_index];
stream->last_key_frame= key_frame;
nut->packet_start[ frame_type ]= frame_start;
stream->last_pts= pts;
}
static void reset(AVFormatContext *s, int64_t global_ts){
NUTContext *nut = s->priv_data;
int i;
for(i=0; i<s->nb_streams; i++){
StreamContext *stream= &nut->stream[i];
stream->last_key_frame= 1;
stream->last_pts= av_rescale(global_ts, stream->rate_num*(int64_t)nut->rate_den, stream->rate_den*(int64_t)nut->rate_num);
}
}
static void build_frame_code(AVFormatContext *s){
NUTContext *nut = s->priv_data;
int key_frame, index, pred, stream_id;
int start=0;
int end= 255;
int keyframe_0_esc= s->nb_streams > 2;
int pred_table[10];
if(keyframe_0_esc){
/* keyframe = 0 escape */
FrameCode *ft= &nut->frame_code[start];
ft->flags= FLAG_DATA_SIZE;
ft->stream_id_plus1= 0;
ft->size_mul=1;
ft->timestamp_delta=0;
start++;
}
for(stream_id= 0; stream_id<s->nb_streams; stream_id++){
int start2= start + (end-start)*stream_id / s->nb_streams;
int end2 = start + (end-start)*(stream_id+1) / s->nb_streams;
AVCodecContext *codec = s->streams[stream_id]->codec;
int is_audio= codec->codec_type == CODEC_TYPE_AUDIO;
int intra_only= /*codec->intra_only || */is_audio;
int pred_count;
for(key_frame=0; key_frame<2; key_frame++){
if(intra_only && keyframe_0_esc && key_frame==0)
continue;
{
FrameCode *ft= &nut->frame_code[start2];
ft->flags= FLAG_KEY_FRAME*key_frame;
ft->flags|= FLAG_DATA_SIZE;
ft->stream_id_plus1= stream_id + 1;
ft->size_mul=1;
ft->timestamp_delta=0;
start2++;
}
}
key_frame= intra_only;
#if 1
if(is_audio){
int frame_bytes= codec->frame_size*(int64_t)codec->bit_rate / (8*codec->sample_rate);
int pts;
for(pts=0; pts<2; pts++){
for(pred=0; pred<2; pred++){
FrameCode *ft= &nut->frame_code[start2];
ft->flags= FLAG_KEY_FRAME*key_frame;
ft->stream_id_plus1= stream_id + 1;
ft->size_mul=frame_bytes + 2;
ft->size_lsb=frame_bytes + pred;
ft->timestamp_delta=pts;
start2++;
}
}
}else{
FrameCode *ft= &nut->frame_code[start2];
ft->flags= FLAG_KEY_FRAME | FLAG_DATA_SIZE;
ft->stream_id_plus1= stream_id + 1;
ft->size_mul=1;
ft->timestamp_delta=1;
start2++;
}
#endif
if(codec->has_b_frames){
pred_count=5;
pred_table[0]=-2;
pred_table[1]=-1;
pred_table[2]=1;
pred_table[3]=3;
pred_table[4]=4;
}else if(codec->codec_id == CODEC_ID_VORBIS){
pred_count=3;
pred_table[0]=2;
pred_table[1]=9;
pred_table[2]=16;
}else{
pred_count=1;
pred_table[0]=1;
}
for(pred=0; pred<pred_count; pred++){
int start3= start2 + (end2-start2)*pred / pred_count;
int end3 = start2 + (end2-start2)*(pred+1) / pred_count;
for(index=start3; index<end3; index++){
FrameCode *ft= &nut->frame_code[index];
ft->flags= FLAG_KEY_FRAME*key_frame;
ft->flags|= FLAG_DATA_SIZE;
ft->stream_id_plus1= stream_id + 1;
//FIXME use single byte size and pred from last
ft->size_mul= end3-start3;
ft->size_lsb= index - start3;
ft->timestamp_delta= pred_table[pred];
}
}
}
memmove(&nut->frame_code['N'+1], &nut->frame_code['N'], sizeof(FrameCode)*(255-'N'));
nut->frame_code['N'].flags= FLAG_INVALID;
}
static uint64_t get_v(ByteIOContext *bc)
{
uint64_t val = 0;
for(;;)
{
int tmp = get_byte(bc);
if (tmp&0x80)
val= (val<<7) + tmp - 0x80;
else{
//av_log(NULL, AV_LOG_DEBUG, "get_v()= %lld\n", (val<<7) + tmp);
return (val<<7) + tmp;
}
}
return -1;
}
static int get_str(ByteIOContext *bc, char *string, unsigned int maxlen){
unsigned int len= get_v(bc);
if(len && maxlen)
get_buffer(bc, string, FFMIN(len, maxlen));
while(len > maxlen){
get_byte(bc);
len--;
}
if(maxlen)
string[FFMIN(len, maxlen-1)]= 0;
if(maxlen == len)
return -1;
else
return 0;
}
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 uint64_t get_vb(ByteIOContext *bc){
uint64_t val=0;
unsigned int i= get_v(bc);
if(i>8)
return UINT64_MAX;
while(i--)
val = (val<<8) + get_byte(bc);
//av_log(NULL, AV_LOG_DEBUG, "get_vb()= %lld\n", val);
return val;
}
#ifdef TRACE
static inline uint64_t get_v_trace(ByteIOContext *bc, char *file, char *func, int line){
uint64_t v= get_v(bc);
printf("get_v %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
return v;
}
static inline int64_t get_s_trace(ByteIOContext *bc, char *file, char *func, int line){
int64_t v= get_s(bc);
printf("get_s %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
return v;
}
static inline uint64_t get_vb_trace(ByteIOContext *bc, char *file, char *func, int line){
uint64_t v= get_vb(bc);
printf("get_vb %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
return v;
}
#define get_v(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define get_vb(bc) get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#endif
static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int calculate_checksum)
{
int64_t start, size;
start= url_ftell(bc) - 8;
size= get_v(bc);
init_checksum(bc, calculate_checksum ? av_adler32_update : NULL, 1);
nut->packet_start[2] = start;
nut->written_packet_size= size;
return size;
}
static int check_checksum(ByteIOContext *bc){
unsigned long checksum= get_checksum(bc);
return checksum != get_be32(bc);
}
/**
*
*/
static int get_length(uint64_t val){
int i;
for (i=7; val>>i; i+=7);
return i;
}
static uint64_t find_any_startcode(ByteIOContext *bc, int64_t pos){
uint64_t state=0;
if(pos >= 0)
url_fseek(bc, pos, SEEK_SET); //note, this may fail if the stream isnt seekable, but that shouldnt matter, as in this case we simply start where we are currently
while(!url_feof(bc)){
state= (state<<8) | get_byte(bc);
if((state>>56) != 'N')
continue;
switch(state){
case MAIN_STARTCODE:
case STREAM_STARTCODE:
case KEYFRAME_STARTCODE:
case INFO_STARTCODE:
case INDEX_STARTCODE:
return state;
}
}
return 0;
}
/**
* find the given startcode.
* @param code the startcode
* @param pos the start position of the search, or -1 if the current position
* @returns the position of the startcode or -1 if not found
*/
static int64_t find_startcode(ByteIOContext *bc, uint64_t code, int64_t pos){
for(;;){
uint64_t startcode= find_any_startcode(bc, pos);
if(startcode == code)
return url_ftell(bc) - 8;
else if(startcode == 0)
return -1;
pos=-1;
}
}
static int64_t lsb2full(StreamContext *stream, int64_t lsb){
int64_t mask = (1<<stream->msb_timestamp_shift)-1;
int64_t delta= stream->last_pts - mask/2;
return ((lsb - delta)&mask) + delta;
}
#ifdef CONFIG_MUXERS
static void put_v(ByteIOContext *bc, uint64_t val)
{
int i;
//av_log(NULL, AV_LOG_DEBUG, "put_v()= %lld\n", val);
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);
}
/**
* stores a string as vb.
*/
static void put_str(ByteIOContext *bc, const char *string){
int len= strlen(string);
put_v(bc, len);
put_buffer(bc, string, len);
}
static void put_s(ByteIOContext *bc, int64_t val){
if (val<=0) put_v(bc, -2*val );
else put_v(bc, 2*val-1);
}
static void put_vb(ByteIOContext *bc, uint64_t val){
int i;
for (i=8; val>>i; i+=8);
put_v(bc, i>>3);
for(i-=8; i>=0; i-=8)
put_byte(bc, (val>>i)&0xFF);
}
#ifdef TRACE
static inline void put_v_trace(ByteIOContext *bc, uint64_t v, char *file, char *func, int line){
printf("get_v %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
put_v(bc, v);
}
static inline void put_s_trace(ByteIOContext *bc, int64_t v, char *file, char *func, int line){
printf("get_s %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
put_s(bc, v);
}
static inline void put_vb_trace(ByteIOContext *bc, uint64_t v, char *file, char *func, int line){
printf("get_vb %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
put_vb(bc, v);
}
#define put_v(bc, v) put_v_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define put_s(bc, v) put_s_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#define put_vb(bc, v) put_vb_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
#endif
static int put_packetheader(NUTContext *nut, ByteIOContext *bc, int max_size, int calculate_checksum)
{
put_flush_packet(bc);
nut->packet_start[2]= url_ftell(bc) - 8;
nut->written_packet_size = max_size;
/* packet header */
put_v(bc, nut->written_packet_size); /* forward ptr */
if(calculate_checksum)
init_checksum(bc, av_adler32_update, 1);
return 0;
}
/**
*
* must not be called more then once per packet
*/
static int update_packetheader(NUTContext *nut, ByteIOContext *bc, int additional_size, int calculate_checksum){
int64_t start= nut->packet_start[2];
int64_t cur= url_ftell(bc);
int size= cur - start - get_length(nut->written_packet_size)/7 - 8;
if(calculate_checksum)
size += 4;
if(size != nut->written_packet_size){
int i;
assert( size <= nut->written_packet_size );
url_fseek(bc, start + 8, SEEK_SET);
for(i=get_length(size); i < get_length(nut->written_packet_size); i+=7)
put_byte(bc, 0x80);
put_v(bc, size);
url_fseek(bc, cur, SEEK_SET);
nut->written_packet_size= size; //FIXME may fail if multiple updates with differing sizes, as get_length may differ
if(calculate_checksum)
put_be32(bc, get_checksum(bc));
}
return 0;
}
static int nut_write_header(AVFormatContext *s)
{
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb;
AVCodecContext *codec;
int i, j, tmp_time, tmp_flags,tmp_stream, tmp_mul, tmp_size, tmp_fields;
if (strcmp(s->filename, "./data/b-libav.nut")) {
av_log(s, AV_LOG_ERROR, " libavformat NUT is non-compliant and disabled\n");
return -1;
}
nut->avf= s;
nut->stream =
av_mallocz(sizeof(StreamContext)*s->nb_streams);
put_buffer(bc, ID_STRING, strlen(ID_STRING));
put_byte(bc, 0);
nut->packet_start[2]= url_ftell(bc);
/* main header */
put_be64(bc, MAIN_STARTCODE);
put_packetheader(nut, bc, 120+5*256, 1);
put_v(bc, 2); /* version */
put_v(bc, s->nb_streams);
put_v(bc, MAX_DISTANCE);
put_v(bc, MAX_SHORT_DISTANCE);
put_v(bc, nut->rate_num=1);
put_v(bc, nut->rate_den=2);
put_v(bc, nut->short_startcode=0x4EFE79);
build_frame_code(s);
assert(nut->frame_code['N'].flags == FLAG_INVALID);
tmp_time= tmp_flags= tmp_stream= tmp_mul= tmp_size= /*tmp_res=*/ INT_MAX;
for(i=0; i<256;){
tmp_fields=0;
tmp_size= 0;
if(tmp_time != nut->frame_code[i].timestamp_delta) tmp_fields=1;
if(tmp_mul != nut->frame_code[i].size_mul ) tmp_fields=2;
if(tmp_stream != nut->frame_code[i].stream_id_plus1) tmp_fields=3;
if(tmp_size != nut->frame_code[i].size_lsb ) tmp_fields=4;
// if(tmp_res != nut->frame_code[i].res ) tmp_fields=5;
tmp_time = nut->frame_code[i].timestamp_delta;
tmp_flags = nut->frame_code[i].flags;
tmp_stream= nut->frame_code[i].stream_id_plus1;
tmp_mul = nut->frame_code[i].size_mul;
tmp_size = nut->frame_code[i].size_lsb;
// tmp_res = nut->frame_code[i].res;
for(j=0; i<256; j++,i++){
if(nut->frame_code[i].timestamp_delta != tmp_time ) break;
if(nut->frame_code[i].flags != tmp_flags ) break;
if(nut->frame_code[i].stream_id_plus1 != tmp_stream) break;
if(nut->frame_code[i].size_mul != tmp_mul ) break;
if(nut->frame_code[i].size_lsb != tmp_size+j) break;
// if(nut->frame_code[i].res != tmp_res ) break;
}
if(j != tmp_mul - tmp_size) tmp_fields=6;
put_v(bc, tmp_flags);
put_v(bc, tmp_fields);
if(tmp_fields>0) put_s(bc, tmp_time);
if(tmp_fields>1) put_v(bc, tmp_mul);
if(tmp_fields>2) put_v(bc, tmp_stream);
if(tmp_fields>3) put_v(bc, tmp_size);
if(tmp_fields>4) put_v(bc, 0 /*tmp_res*/);
if(tmp_fields>5) put_v(bc, j);
}
update_packetheader(nut, bc, 0, 1);
/* stream headers */
for (i = 0; i < s->nb_streams; i++)
{
int nom, denom, ssize;
codec = s->streams[i]->codec;
put_be64(bc, STREAM_STARTCODE);
put_packetheader(nut, bc, 120 + codec->extradata_size, 1);
put_v(bc, i /*s->streams[i]->index*/);
switch(codec->codec_type){
case CODEC_TYPE_VIDEO: put_v(bc, 0); break;
case CODEC_TYPE_AUDIO: put_v(bc, 1); break;
// case CODEC_TYPE_TEXT : put_v(bc, 2); break;
case CODEC_TYPE_DATA : put_v(bc, 3); break;
default: return -1;
}
if (codec->codec_tag)
put_vb(bc, codec->codec_tag);
else if (codec->codec_type == CODEC_TYPE_VIDEO)
{
put_vb(bc, codec_get_bmp_tag(codec->codec_id));
}
else if (codec->codec_type == CODEC_TYPE_AUDIO)
{
put_vb(bc, codec_get_wav_tag(codec->codec_id));
}
else
put_vb(bc, 0);
ff_parse_specific_params(codec, &nom, &ssize, &denom);
nut->stream[i].rate_num= nom;
nut->stream[i].rate_den= denom;
av_set_pts_info(s->streams[i], 60, denom, nom);
put_v(bc, codec->bit_rate);
put_vb(bc, 0); /* no language code */
put_v(bc, nom);
put_v(bc, denom);
if(nom / denom < 1000)
nut->stream[i].msb_timestamp_shift = 7;
else
nut->stream[i].msb_timestamp_shift = 14;
put_v(bc, nut->stream[i].msb_timestamp_shift);
put_v(bc, codec->has_b_frames);
put_byte(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */
if(codec->extradata_size){
put_v(bc, 1);
put_v(bc, codec->extradata_size);
put_buffer(bc, codec->extradata, codec->extradata_size);
}
put_v(bc, 0); /* end of codec specific headers */
switch(codec->codec_type)
{
case CODEC_TYPE_AUDIO:
put_v(bc, codec->sample_rate);
put_v(bc, 1);
put_v(bc, codec->channels);
break;
case CODEC_TYPE_VIDEO:
put_v(bc, codec->width);
put_v(bc, codec->height);
put_v(bc, codec->sample_aspect_ratio.num);
put_v(bc, codec->sample_aspect_ratio.den);
put_v(bc, 0); /* csp type -- unknown */
break;
default:
break;
}
update_packetheader(nut, bc, 0, 1);
}
/* info header */
put_be64(bc, INFO_STARTCODE);
put_packetheader(nut, bc, 30+strlen(s->author)+strlen(s->title)+
strlen(s->comment)+strlen(s->copyright)+strlen(LIBAVFORMAT_IDENT), 1);
if (s->author[0])
{
put_v(bc, 9); /* type */
put_str(bc, s->author);
}
if (s->title[0])
{
put_v(bc, 10); /* type */
put_str(bc, s->title);
}
if (s->comment[0])
{
put_v(bc, 11); /* type */
put_str(bc, s->comment);
}
if (s->copyright[0])
{
put_v(bc, 12); /* type */
put_str(bc, s->copyright);
}
/* encoder */
if(!(s->streams[0]->codec->flags & CODEC_FLAG_BITEXACT)){
put_v(bc, 13); /* type */
put_str(bc, LIBAVFORMAT_IDENT);
}
put_v(bc, 0); /* eof info */
update_packetheader(nut, bc, 0, 1);
put_flush_packet(bc);
return 0;
}
static int nut_write_packet(AVFormatContext *s, AVPacket *pkt)
{
NUTContext *nut = s->priv_data;
StreamContext *stream= &nut->stream[pkt->stream_index];
ByteIOContext *bc = &s->pb;
int key_frame = 0, full_pts=0;
AVCodecContext *enc;
int64_t coded_pts;
int frame_type, best_length, frame_code, flags, i, size_mul, size_lsb, time_delta;
const int64_t frame_start= url_ftell(bc);
int64_t pts= pkt->pts;
int size= pkt->size;
int stream_index= pkt->stream_index;
enc = s->streams[stream_index]->codec;
key_frame = !!(pkt->flags & PKT_FLAG_KEY);
frame_type=0;
if(frame_start + size + 20 - FFMAX(nut->packet_start[1], nut->packet_start[2]) > MAX_DISTANCE)
frame_type=2;
if(key_frame && !stream->last_key_frame)
frame_type=2;
if(frame_type>1){
int64_t global_ts= av_rescale(pts, stream->rate_den*(int64_t)nut->rate_num, stream->rate_num*(int64_t)nut->rate_den);
reset(s, global_ts);
put_be64(bc, KEYFRAME_STARTCODE);
put_v(bc, global_ts);
}
assert(stream->last_pts != AV_NOPTS_VALUE);
coded_pts = pts & ((1<<stream->msb_timestamp_shift)-1);
if(lsb2full(stream, coded_pts) != pts)
full_pts=1;
if(full_pts)
coded_pts= pts + (1<<stream->msb_timestamp_shift);
best_length=INT_MAX;
frame_code= -1;
for(i=0; i<256; i++){
int stream_id_plus1= nut->frame_code[i].stream_id_plus1;
int fc_key_frame;
int length=0;
size_mul= nut->frame_code[i].size_mul;
size_lsb= nut->frame_code[i].size_lsb;
time_delta= nut->frame_code[i].timestamp_delta;
flags= nut->frame_code[i].flags;
assert(size_mul > size_lsb);
if(stream_id_plus1 == 0) length+= get_length(stream_index);
else if(stream_id_plus1 - 1 != stream_index)
continue;
fc_key_frame= !!(flags & FLAG_KEY_FRAME);
assert(key_frame==0 || key_frame==1);
if(fc_key_frame != key_frame)
continue;
if(flags & FLAG_DATA_SIZE){
if(size % size_mul != size_lsb)
continue;
length += get_length(size / size_mul);
}else if(size != size_lsb)
continue;
if(full_pts && time_delta)
continue;
if(!time_delta){
length += get_length(coded_pts);
}else{
if(time_delta != pts - stream->last_pts)
continue;
}
if(length < best_length){
best_length= length;
frame_code=i;
}
// av_log(s, AV_LOG_DEBUG, "%d %d %d %d %d %d %d %d %d %d\n", key_frame, frame_type, full_pts, size, stream_index, flags, size_mul, size_lsb, stream_id_plus1, length);
}
assert(frame_code != -1);
flags= nut->frame_code[frame_code].flags;
size_mul= nut->frame_code[frame_code].size_mul;
size_lsb= nut->frame_code[frame_code].size_lsb;
time_delta= nut->frame_code[frame_code].timestamp_delta;
#ifdef TRACE
best_length /= 7;
best_length ++; //frame_code
if(frame_type==2){
best_length += 8; // startcode
}
av_log(s, AV_LOG_DEBUG, "kf:%d ft:%d pt:%d fc:%2X len:%2d size:%d stream:%d flag:%d mul:%d lsb:%d s+1:%d pts_delta:%d pts:%lld fs:%lld\n", key_frame, frame_type, full_pts ? 1 : 0, frame_code, best_length, size, stream_index, flags, size_mul, size_lsb, nut->frame_code[frame_code].stream_id_plus1,(int)(pts - stream->last_pts), pts, frame_start);
// av_log(s, AV_LOG_DEBUG, "%d %d %d\n", stream->lru_pts_delta[0], stream->lru_pts_delta[1], stream->lru_pts_delta[2]);
#endif
assert(frame_type != 1); //short startcode not implemented yet
put_byte(bc, frame_code);
if(nut->frame_code[frame_code].stream_id_plus1 == 0)
put_v(bc, stream_index);
if (!time_delta){
put_v(bc, coded_pts);
}
if(flags & FLAG_DATA_SIZE)
put_v(bc, size / size_mul);
else
assert(size == size_lsb);
if(size > MAX_DISTANCE){
assert(frame_type > 1);
}
put_buffer(bc, pkt->data, size);
update(nut, stream_index, frame_start, frame_type, frame_code, key_frame, size, pts);
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, 1);
put_v(bc, s->streams[i]->id);
put_v(bc, ...);
update_packetheader(nut, bc, 0, 1);
}
#endif
put_flush_packet(bc);
av_freep(&nut->stream);
return 0;
}
#endif //CONFIG_MUXERS
static int nut_probe(AVProbeData *p)
{
int i;
uint64_t code= 0xff;
for (i = 0; i < p->buf_size; i++) {
code = (code << 8) | p->buf[i];
if (code == MAIN_STARTCODE)
return AVPROBE_SCORE_MAX;
}
return 0;
}
static int decode_main_header(NUTContext *nut){
AVFormatContext *s= nut->avf;
ByteIOContext *bc = &s->pb;
uint64_t tmp;
int i, j, tmp_stream, tmp_mul, tmp_time, tmp_size, count, tmp_res;
get_packetheader(nut, bc, 1);
tmp = get_v(bc);
if (tmp != 2){
av_log(s, AV_LOG_ERROR, "bad version (%"PRId64")\n", tmp);
return -1;
}
nut->stream_count = get_v(bc);
if(nut->stream_count > MAX_STREAMS){
av_log(s, AV_LOG_ERROR, "too many streams\n");
return -1;
}
nut->max_distance = get_v(bc);
nut->max_short_distance = get_v(bc);
nut->rate_num= get_v(bc);
nut->rate_den= get_v(bc);
nut->short_startcode= get_v(bc);
if(nut->short_startcode>>16 != 'N'){
av_log(s, AV_LOG_ERROR, "invalid short startcode %X\n", nut->short_startcode);
return -1;
}
for(i=0; i<256;){
int tmp_flags = get_v(bc);
int tmp_fields= get_v(bc);
if(tmp_fields>0) tmp_time = get_s(bc);
if(tmp_fields>1) tmp_mul = get_v(bc);
if(tmp_fields>2) tmp_stream= get_v(bc);
if(tmp_fields>3) tmp_size = get_v(bc);
else tmp_size = 0;
if(tmp_fields>4) tmp_res = get_v(bc);
else tmp_res = 0;
if(tmp_fields>5) count = get_v(bc);
else count = tmp_mul - tmp_size;
while(tmp_fields-- > 6)
get_v(bc);
if(count == 0 || i+count > 256){
av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
return -1;
}
if(tmp_stream > nut->stream_count + 1){
av_log(s, AV_LOG_ERROR, "illegal stream number\n");
return -1;
}
for(j=0; j<count; j++,i++){
nut->frame_code[i].flags = tmp_flags ;
nut->frame_code[i].timestamp_delta = tmp_time ;
nut->frame_code[i].stream_id_plus1 = tmp_stream;
nut->frame_code[i].size_mul = tmp_mul ;
nut->frame_code[i].size_lsb = tmp_size+j;
nut->frame_code[i].reserved_count = tmp_res ;
}
}
if(nut->frame_code['N'].flags != FLAG_INVALID){
av_log(s, AV_LOG_ERROR, "illegal frame_code table\n");
return -1;
}
if(check_checksum(bc)){
av_log(s, AV_LOG_ERROR, "Main header checksum mismatch\n");
return -1;
}
return 0;
}
static int decode_stream_header(NUTContext *nut){
AVFormatContext *s= nut->avf;
ByteIOContext *bc = &s->pb;
int class, nom, denom, stream_id;
uint64_t tmp;
AVStream *st;
get_packetheader(nut, bc, 1);
stream_id= get_v(bc);
if(stream_id >= nut->stream_count || s->streams[stream_id])
return -1;
st = av_new_stream(s, stream_id);
if (!st)
return AVERROR_NOMEM;
class = get_v(bc);
tmp = get_vb(bc);
st->codec->codec_tag= tmp;
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)
av_log(s, AV_LOG_ERROR, "Unknown codec?!\n");
break;
case 1:
case 32: //compatibility
st->codec->codec_type = CODEC_TYPE_AUDIO;
st->codec->codec_id = codec_get_wav_id(tmp);
if (st->codec->codec_id == CODEC_ID_NONE)
av_log(s, AV_LOG_ERROR, "Unknown codec?!\n");
break;
case 2:
// st->codec->codec_type = CODEC_TYPE_TEXT;
// break;
case 3:
st->codec->codec_type = CODEC_TYPE_DATA;
break;
default:
av_log(s, AV_LOG_ERROR, "Unknown stream class (%d)\n", class);
return -1;
}
s->bit_rate += get_v(bc);
get_vb(bc); /* language code */
nom = get_v(bc);
denom = get_v(bc);
nut->stream[stream_id].msb_timestamp_shift = get_v(bc);
st->codec->has_b_frames=
nut->stream[stream_id].decode_delay= get_v(bc);
get_byte(bc); /* flags */
/* codec specific data headers */
while(get_v(bc) != 0){
st->codec->extradata_size= get_v(bc);
if((unsigned)st->codec->extradata_size > (1<<30))
return -1;
st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
get_buffer(bc, st->codec->extradata, st->codec->extradata_size);
// url_fskip(bc, get_v(bc));
}
if (st->codec->codec_type == CODEC_TYPE_VIDEO) /* VIDEO */
{
st->codec->width = get_v(bc);
st->codec->height = get_v(bc);
st->codec->sample_aspect_ratio.num= get_v(bc);
st->codec->sample_aspect_ratio.den= get_v(bc);
get_v(bc); /* csp type */
}
if (st->codec->codec_type == CODEC_TYPE_AUDIO) /* AUDIO */
{
st->codec->sample_rate = get_v(bc);
get_v(bc); // samplerate_den
st->codec->channels = get_v(bc);
}
if(check_checksum(bc)){
av_log(s, AV_LOG_ERROR, "Stream header %d checksum mismatch\n", stream_id);
return -1;
}
av_set_pts_info(s->streams[stream_id], 60, denom, nom);
nut->stream[stream_id].rate_num= nom;
nut->stream[stream_id].rate_den= denom;
return 0;
}
static int decode_info_header(NUTContext *nut){
AVFormatContext *s= nut->avf;
ByteIOContext *bc = &s->pb;
get_packetheader(nut, bc, 1);
for(;;){
int id= get_v(bc);
char *name, *type, custom_name[256], custom_type[256];
if(!id)
break;
else if(id >= sizeof(info_table)/sizeof(info_table[0])){
av_log(s, AV_LOG_ERROR, "info id is too large %d %zd\n", id, sizeof(info_table)/sizeof(info_table[0]));
return -1;
}
type= info_table[id][1];
name= info_table[id][0];
//av_log(s, AV_LOG_DEBUG, "%d %s %s\n", id, type, name);
if(!type){
get_str(bc, custom_type, sizeof(custom_type));
type= custom_type;
}
if(!name){
get_str(bc, custom_name, sizeof(custom_name));
name= custom_name;
}
if(!strcmp(type, "v")){
get_v(bc);
}else{
if(!strcmp(name, "Author"))
get_str(bc, s->author, sizeof(s->author));
else if(!strcmp(name, "Title"))
get_str(bc, s->title, sizeof(s->title));
else if(!strcmp(name, "Copyright"))
get_str(bc, s->copyright, sizeof(s->copyright));
else if(!strcmp(name, "Description"))
get_str(bc, s->comment, sizeof(s->comment));
else
get_str(bc, NULL, 0);
}
}
if(check_checksum(bc)){
av_log(s, AV_LOG_ERROR, "Info header checksum mismatch\n");
return -1;
}
return 0;
}
static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb;
int64_t pos;
int inited_stream_count;
nut->avf= s;
/* main header */
pos=0;
for(;;){
pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
if (pos<0){
av_log(s, AV_LOG_ERROR, "no main startcode found\n");
return -1;
}
if(decode_main_header(nut) >= 0)
break;
}
s->bit_rate = 0;
nut->stream = av_malloc(sizeof(StreamContext)*nut->stream_count);
/* stream headers */
pos=0;
for(inited_stream_count=0; inited_stream_count < nut->stream_count;){
pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
if (pos<0+1){
av_log(s, AV_LOG_ERROR, "not all stream headers found\n");
return -1;
}
if(decode_stream_header(nut) >= 0)
inited_stream_count++;
}
/* info headers */
pos=0;
for(;;){
uint64_t startcode= find_any_startcode(bc, pos);
pos= url_ftell(bc);
if(startcode==0){
av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
return -1;
}else if(startcode == KEYFRAME_STARTCODE){
nut->next_startcode= startcode;
break;
}else if(startcode != INFO_STARTCODE){
continue;
}
decode_info_header(nut);
}
return 0;
}
static int decode_frame_header(NUTContext *nut, int *key_frame_ret, int64_t *pts_ret, int *stream_id_ret, int frame_code, int frame_type, int64_t frame_start){
AVFormatContext *s= nut->avf;
StreamContext *stream;
ByteIOContext *bc = &s->pb;
int size, flags, size_mul, size_lsb, stream_id, time_delta;
int64_t pts = 0;
if(frame_type < 2 && frame_start - nut->packet_start[2] > nut->max_distance){
av_log(s, AV_LOG_ERROR, "last frame must have been damaged\n");
return -1;
}
if(frame_type)
nut->packet_start[ frame_type ]= frame_start; //otherwise 1 goto 1 may happen
flags= nut->frame_code[frame_code].flags;
size_mul= nut->frame_code[frame_code].size_mul;
size_lsb= nut->frame_code[frame_code].size_lsb;
stream_id= nut->frame_code[frame_code].stream_id_plus1 - 1;
time_delta= nut->frame_code[frame_code].timestamp_delta;
if(stream_id==-1)
stream_id= get_v(bc);
if(stream_id >= s->nb_streams){
av_log(s, AV_LOG_ERROR, "illegal stream_id\n");
return -1;
}
stream= &nut->stream[stream_id];
// av_log(s, AV_LOG_DEBUG, "ft:%d ppts:%d %d %d\n", frame_type, stream->lru_pts_delta[0], stream->lru_pts_delta[1], stream->lru_pts_delta[2]);
*key_frame_ret= !!(flags & FLAG_KEY_FRAME);
if(!time_delta){
int64_t mask = (1<<stream->msb_timestamp_shift)-1;
pts= get_v(bc);
if(pts > mask){
pts -= mask+1;
}else{
if(stream->last_pts == AV_NOPTS_VALUE){
av_log(s, AV_LOG_ERROR, "no reference pts available\n");
return -1;
}
pts= lsb2full(stream, pts);
}
}else{
if(stream->last_pts == AV_NOPTS_VALUE){
av_log(s, AV_LOG_ERROR, "no reference pts available\n");
return -1;
}
pts= stream->last_pts + time_delta;
}
if(*key_frame_ret){
// av_log(s, AV_LOG_DEBUG, "stream:%d start:%lld pts:%lld length:%lld\n",stream_id, frame_start, av_pts, frame_start - nut->stream[stream_id].last_sync_pos);
av_add_index_entry(
s->streams[stream_id],
frame_start,
pts,
0,
frame_start - nut->stream[stream_id].last_sync_pos,
AVINDEX_KEYFRAME);
nut->stream[stream_id].last_sync_pos= frame_start;
// assert(nut->packet_start == frame_start);
}
assert(size_mul > size_lsb);
size= size_lsb;
if(flags & FLAG_DATA_SIZE)
size+= size_mul*get_v(bc);
#ifdef TRACE
av_log(s, AV_LOG_DEBUG, "fs:%lld fc:%d ft:%d kf:%d pts:%lld size:%d mul:%d lsb:%d flags:%d delta:%d\n", frame_start, frame_code, frame_type, *key_frame_ret, pts, size, size_mul, size_lsb, flags, time_delta);
#endif
if(frame_type==0 && url_ftell(bc) - nut->packet_start[2] + size > nut->max_distance){
av_log(s, AV_LOG_ERROR, "frame size too large\n");
return -1;
}
*stream_id_ret = stream_id;
*pts_ret = pts;
update(nut, stream_id, frame_start, frame_type, frame_code, *key_frame_ret, size, pts);
return size;
}
static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code, int frame_type, int64_t frame_start){
AVFormatContext *s= nut->avf;
ByteIOContext *bc = &s->pb;
int size, stream_id, key_frame, discard;
int64_t pts, last_IP_pts;
size= decode_frame_header(nut, &key_frame, &pts, &stream_id, frame_code, frame_type, frame_start);
if(size < 0)
return -1;
discard= s->streams[ stream_id ]->discard;
last_IP_pts= s->streams[ stream_id ]->last_IP_pts;
if( (discard >= AVDISCARD_NONKEY && !key_frame)
||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts)
|| discard >= AVDISCARD_ALL){
url_fskip(bc, size);
return 1;
}
av_get_packet(bc, pkt, size);
pkt->stream_index = stream_id;
if (key_frame)
pkt->flags |= PKT_FLAG_KEY;
pkt->pts = pts;
return 0;
}
static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
{
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb;
int i, frame_code=0, ret;
for(;;){
int64_t pos= url_ftell(bc);
int frame_type= 0;
uint64_t tmp= nut->next_startcode;
nut->next_startcode=0;
if (url_feof(bc))
return -1;
if(tmp){
pos-=8;
}else{
frame_code = get_byte(bc);
if(frame_code == 'N'){
tmp= frame_code;
for(i=1; i<8; i++)
tmp = (tmp<<8) + get_byte(bc);
}
}
switch(tmp){
case MAIN_STARTCODE:
case STREAM_STARTCODE:
case INDEX_STARTCODE:
get_packetheader(nut, bc, 0);
assert(nut->packet_start[2] == pos);
url_fseek(bc, nut->written_packet_size, SEEK_CUR);
break;
case INFO_STARTCODE:
if(decode_info_header(nut)<0)
goto resync;
break;
case KEYFRAME_STARTCODE:
frame_type = 2;
reset(s, get_v(bc));
frame_code = get_byte(bc);
case 0:
ret= decode_frame(nut, pkt, frame_code, frame_type, pos);
if(ret==0)
return 0;
else if(ret==1) //ok but discard packet
break;
default:
resync:
av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", nut->packet_start[2]+1);
tmp= find_any_startcode(bc, nut->packet_start[2]+1);
if(tmp==0)
return -1;
av_log(s, AV_LOG_DEBUG, "sync\n");
nut->next_startcode= tmp;
}
}
}
static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
NUTContext *nut = s->priv_data;
StreamContext *stream;
ByteIOContext *bc = &s->pb;
int64_t pos, pts;
uint64_t code;
int frame_code,step, stream_id, i,size, key_frame;
av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit);
if(*pos_arg < 0)
return AV_NOPTS_VALUE;
pos= *pos_arg;
step= FFMIN(16*1024, pos);
do{
pos-= step;
code= find_any_startcode(bc, pos);
if(code && url_ftell(bc) - 8 <= *pos_arg)
break;
step= FFMIN(2*step, pos);
}while(step);
if(!code) //nothing found, not even after pos_arg
return AV_NOPTS_VALUE;
url_fseek(bc, -8, SEEK_CUR);
for(i=0; i<s->nb_streams; i++)
nut->stream[i].last_sync_pos= url_ftell(bc);
for(;;){
int frame_type=0;
int64_t pos= url_ftell(bc);
uint64_t tmp=0;
if(pos > pos_limit || url_feof(bc))
return AV_NOPTS_VALUE;
frame_code = get_byte(bc);
if(frame_code == 'N'){
tmp= frame_code;
for(i=1; i<8; i++)
tmp = (tmp<<8) + get_byte(bc);
}
//av_log(s, AV_LOG_DEBUG, "before switch %llX at=%lld\n", tmp, pos);
switch(tmp){
case MAIN_STARTCODE:
case STREAM_STARTCODE:
case INDEX_STARTCODE:
case INFO_STARTCODE:
get_packetheader(nut, bc, 0);
assert(nut->packet_start[2]==pos);
url_fseek(bc, nut->written_packet_size, SEEK_CUR);
break;
case KEYFRAME_STARTCODE:
frame_type=2;
reset(s, get_v(bc));
frame_code = get_byte(bc);
case 0:
size= decode_frame_header(nut, &key_frame, &pts, &stream_id, frame_code, frame_type, pos);
if(size < 0)
goto resync;
stream= &nut->stream[stream_id];
if(stream_id != stream_index || !key_frame || pos < *pos_arg){
url_fseek(bc, size, SEEK_CUR);
break;
}
*pos_arg= pos;
return pts;
default:
resync:
av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", nut->packet_start[2]+1);
if(!find_any_startcode(bc, nut->packet_start[2]+1))
return AV_NOPTS_VALUE;
url_fseek(bc, -8, SEEK_CUR);
}
}
return AV_NOPTS_VALUE;
}
static int nut_read_seek(AVFormatContext *s, int stream_index, int64_t target_ts, int flags){
// NUTContext *nut = s->priv_data;
int64_t pos;
if(av_seek_frame_binary(s, stream_index, target_ts, flags) < 0)
return -1;
pos= url_ftell(&s->pb);
nut_read_timestamp(s, stream_index, &pos, pos-1);
return 0;
}
static int nut_read_close(AVFormatContext *s)
{
NUTContext *nut = s->priv_data;
av_freep(&nut->stream);
return 0;
}
#ifdef CONFIG_NUT_DEMUXER
AVInputFormat nut_demuxer = {
"nut",
"nut format",
sizeof(NUTContext),
nut_probe,
nut_read_header,
nut_read_packet,
nut_read_close,
nut_read_seek,
nut_read_timestamp,
.extensions = "nut",
};
#endif
#ifdef CONFIG_NUT_MUXER
AVOutputFormat nut_muxer = {
"nut",
"nut format",
"video/x-nut",
"nut",
sizeof(NUTContext),
#ifdef CONFIG_LIBVORBIS
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,
.flags = AVFMT_GLOBALHEADER,
};
#endif
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