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/*
* nut muxer
* Copyright (c) 2004-2007 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
*/
#include "nut.h"
#define TRACE
static void build_frame_code(AVFormatContext *s){
NUTContext *nut = s->priv_data;
int key_frame, index, pred, stream_id;
int start=1;
int end= 254;
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_STREAM_ID | FLAG_SIZE_MSB | FLAG_CODED_PTS;
ft->size_mul=1;
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*key_frame;
ft->flags|= FLAG_SIZE_MSB | FLAG_CODED_PTS;
ft->stream_id= stream_id;
ft->size_mul=1;
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*key_frame;
ft->stream_id= stream_id;
ft->size_mul=frame_bytes + 2;
ft->size_lsb=frame_bytes + pred;
ft->pts_delta=pts;
start2++;
}
}
}else{
FrameCode *ft= &nut->frame_code[start2];
ft->flags= FLAG_KEY | FLAG_SIZE_MSB;
ft->stream_id= stream_id;
ft->size_mul=1;
ft->pts_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*key_frame;
ft->flags|= FLAG_SIZE_MSB;
ft->stream_id= stream_id;
//FIXME use single byte size and pred from last
ft->size_mul= end3-start3;
ft->size_lsb= index - start3;
ft->pts_delta= pred_table[pred];
}
}
}
memmove(&nut->frame_code['N'+1], &nut->frame_code['N'], sizeof(FrameCode)*(255-'N'));
nut->frame_code[ 0].flags=
nut->frame_code[255].flags=
nut->frame_code['N'].flags= FLAG_INVALID;
}
/**
* Gets the length in bytes which is needed to store val as v.
*/
static int get_length(uint64_t val){
int i=1;
while(val>>=7)
i++;
return i;
}
static void put_v(ByteIOContext *bc, uint64_t val){
int i= get_length(val);
while(--i>0)
put_byte(bc, 128 | (val>>(7*i)));
put_byte(bc, val&127);
}
/**
* 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){
put_v(bc, 2*FFABS(val) - (val>0));
}
#ifdef TRACE
static inline void put_v_trace(ByteIOContext *bc, uint64_t v, char *file, char *func, int line){
printf("get_v %5"PRId64" / %"PRIX64" 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 %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
put_s(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__)
#endif
static void put_packet(NUTContext *nut, ByteIOContext *bc, ByteIOContext *dyn_bc, int calculate_checksum){
uint8_t *dyn_buf=NULL;
int dyn_size= url_close_dyn_buf(dyn_bc, &dyn_buf);
int forw_ptr= dyn_size + 4*calculate_checksum;
if(forw_ptr > 4096)
init_checksum(bc, av_crc04C11DB7_update, 0);
put_v(bc, forw_ptr);
if(forw_ptr > 4096)
put_le32(bc, get_checksum(bc));
if(calculate_checksum)
init_checksum(bc, av_crc04C11DB7_update, 0);
put_buffer(bc, dyn_buf, dyn_size);
if(calculate_checksum)
put_le32(bc, get_checksum(bc));
av_free(dyn_buf);
}
static void write_mainheader(NUTContext *nut, ByteIOContext *bc){
int i, j, tmp_pts, tmp_flags, tmp_stream, tmp_mul, tmp_size, tmp_fields;
put_v(bc, 2); /* version */
put_v(bc, nut->avf->nb_streams);
put_v(bc, MAX_DISTANCE);
put_v(bc, nut->time_base_count);
for(i=0; i<nut->time_base_count; i++){
put_v(bc, nut->time_base[i].num);
put_v(bc, nut->time_base[i].den);
}
tmp_pts=0;
tmp_mul=1;
tmp_stream=0;
for(i=0; i<256;){
tmp_fields=0;
tmp_size=0;
// tmp_res=0;
if(tmp_pts != nut->frame_code[i].pts_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) 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_pts = nut->frame_code[i].pts_delta;
tmp_flags = nut->frame_code[i].flags;
tmp_stream= nut->frame_code[i].stream_id;
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(i == 'N'){
j--;
continue;
}
if(nut->frame_code[i].pts_delta != tmp_pts ) break;
if(nut->frame_code[i].flags != tmp_flags ) break;
if(nut->frame_code[i].stream_id != 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_pts);
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);
}
}
static int write_streamheader(NUTContext *nut, ByteIOContext *bc, AVCodecContext *codec, int i){
put_v(bc, i);
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;
default : put_v(bc, 3); break;
}
put_v(bc, 4);
if (codec->codec_tag){
put_le32(bc, codec->codec_tag);
}else
return -1;
put_v(bc, (nut->stream[i].time_base - nut->time_base)/sizeof(AVRational));
put_v(bc, nut->stream[i].msb_pts_shift);
put_v(bc, nut->stream[i].max_pts_distance);
put_v(bc, codec->has_b_frames);
put_byte(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */
put_v(bc, codec->extradata_size);
put_buffer(bc, codec->extradata, codec->extradata_size);
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;
}
return 0;
}
static int write_header(AVFormatContext *s){
NUTContext *nut = s->priv_data;
ByteIOContext *bc = &s->pb, dyn_bc;
AVCodecContext *codec;
int i, j;
nut->avf= s;
nut->stream = av_mallocz(sizeof(StreamContext)*s->nb_streams);
nut->time_base= av_mallocz(sizeof(AVRational )*s->nb_streams);
for(i=0; i<s->nb_streams; i++){
AVStream *st= s->streams[i];
int ssize;
AVRational time_base;
ff_parse_specific_params(st->codec, &time_base.den, &ssize, &time_base.num);
av_set_pts_info(st, 64, time_base.num, time_base.den);
for(j=0; j<nut->time_base_count; j++){
if(!memcmp(&time_base, &nut->time_base[j], sizeof(AVRational))){
break;
}
}
nut->time_base[j]= time_base;
nut->stream[i].time_base= &nut->time_base[j];
if(j==nut->time_base_count)
nut->time_base_count++;
if(av_q2d(time_base) >= 0.001)
nut->stream[i].msb_pts_shift = 7;
else
nut->stream[i].msb_pts_shift = 14;
nut->stream[i].max_pts_distance= FFMAX(1/av_q2d(time_base), 1);
}
build_frame_code(s);
assert(nut->frame_code['N'].flags == FLAG_INVALID);
put_buffer(bc, ID_STRING, strlen(ID_STRING));
put_byte(bc, 0);
/* main header */
put_be64(bc, MAIN_STARTCODE);
url_open_dyn_buf(&dyn_bc);
write_mainheader(nut, &dyn_bc);
put_packet(nut, bc, &dyn_bc, 1);
for (i=0; i < s->nb_streams; i++){
codec = s->streams[i]->codec;
put_be64(bc, STREAM_STARTCODE);
url_open_dyn_buf(&dyn_bc);
write_streamheader(nut, &dyn_bc, codec, i);
put_packet(nut, bc, &dyn_bc, 1);
}
put_flush_packet(bc);
//FIXME info header, header repeation, ...
return 0;
}
static int write_packet(AVFormatContext *s, AVPacket *pkt){
//FIXME
return 0;
}
AVOutputFormat nut_muxer = {
"nut",
"nut format",
"video/x-nut",
"nut",
sizeof(NUTContext),
#ifdef CONFIG_LIBVORBIS
CODEC_ID_VORBIS,
#elif defined(CONFIG_LIBMP3LAME)
CODEC_ID_MP3,
#else
CODEC_ID_MP2, /* AC3 needs liba52 decoder */
#endif
CODEC_ID_MPEG4,
write_header,
write_packet,
// write_trailer,
.flags = AVFMT_GLOBALHEADER,
.codec_tag= (const AVCodecTag*[]){codec_bmp_tags, codec_wav_tags, 0},
};