mirror of
https://git.ffmpeg.org/ffmpeg.git
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09770af869
Originally committed as revision 2251 to svn://svn.ffmpeg.org/ffmpeg/trunk
700 lines
18 KiB
C
700 lines
18 KiB
C
/*
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* utils for libavcodec
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* Copyright (c) 2001 Fabrice Bellard.
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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/**
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* @file utils.c
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* utils.
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*/
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#include "avcodec.h"
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#include "dsputil.h"
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#include "mpegvideo.h"
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void *av_mallocz(unsigned int size)
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{
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void *ptr;
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ptr = av_malloc(size);
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if (!ptr)
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return NULL;
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memset(ptr, 0, size);
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return ptr;
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}
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char *av_strdup(const char *s)
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{
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char *ptr;
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int len;
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len = strlen(s) + 1;
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ptr = av_malloc(len);
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if (!ptr)
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return NULL;
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memcpy(ptr, s, len);
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return ptr;
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}
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/**
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* realloc which does nothing if the block is large enough
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*/
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void *av_fast_realloc(void *ptr, unsigned int *size, unsigned int min_size)
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{
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if(min_size < *size)
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return ptr;
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*size= min_size + 10*1024;
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return av_realloc(ptr, *size);
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}
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/* allocation of static arrays - do not use for normal allocation */
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static unsigned int last_static = 0;
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static char*** array_static = NULL;
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static const unsigned int grow_static = 64; // ^2
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void *__av_mallocz_static(void** location, unsigned int size)
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{
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unsigned int l = (last_static + grow_static) & ~(grow_static - 1);
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void *ptr = av_mallocz(size);
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if (!ptr)
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return NULL;
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if (location)
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{
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if (l > last_static)
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array_static = av_realloc(array_static, l);
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array_static[last_static++] = (char**) location;
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*location = ptr;
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}
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return ptr;
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}
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/* free all static arrays and reset pointers to 0 */
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void av_free_static(void)
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{
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if (array_static)
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{
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unsigned i;
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for (i = 0; i < last_static; i++)
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{
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av_free(*array_static[i]);
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*array_static[i] = NULL;
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}
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av_free(array_static);
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array_static = 0;
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}
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last_static = 0;
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}
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/* cannot call it directly because of 'void **' casting is not automatic */
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void __av_freep(void **ptr)
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{
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av_free(*ptr);
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*ptr = NULL;
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}
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/* encoder management */
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AVCodec *first_avcodec;
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void register_avcodec(AVCodec *format)
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{
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AVCodec **p;
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p = &first_avcodec;
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while (*p != NULL) p = &(*p)->next;
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*p = format;
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format->next = NULL;
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}
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typedef struct InternalBuffer{
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int last_pic_num;
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uint8_t *base[4];
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uint8_t *data[4];
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}InternalBuffer;
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#define INTERNAL_BUFFER_SIZE 32
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int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic){
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int i;
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const int width = s->width;
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const int height= s->height;
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InternalBuffer *buf;
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assert(pic->data[0]==NULL);
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assert(INTERNAL_BUFFER_SIZE > s->internal_buffer_count);
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if(s->internal_buffer==NULL){
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s->internal_buffer= av_mallocz(INTERNAL_BUFFER_SIZE*sizeof(InternalBuffer));
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}
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#if 0
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s->internal_buffer= av_fast_realloc(
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s->internal_buffer,
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&s->internal_buffer_size,
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sizeof(InternalBuffer)*FFMAX(99, s->internal_buffer_count+1)/*FIXME*/
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);
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#endif
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buf= &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
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if(buf->base[0]){
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pic->age= pic->coded_picture_number - buf->last_pic_num;
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buf->last_pic_num= pic->coded_picture_number;
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}else{
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int align, h_chroma_shift, v_chroma_shift;
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int w, h, pixel_size;
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avcodec_get_chroma_sub_sample(s->pix_fmt, &h_chroma_shift, &v_chroma_shift);
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switch(s->pix_fmt){
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case PIX_FMT_RGB555:
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case PIX_FMT_RGB565:
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case PIX_FMT_YUV422:
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pixel_size=2;
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break;
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case PIX_FMT_RGB24:
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case PIX_FMT_BGR24:
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pixel_size=3;
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break;
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case PIX_FMT_RGBA32:
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pixel_size=4;
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break;
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default:
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pixel_size=1;
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}
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if(s->codec_id==CODEC_ID_SVQ1) align=63;
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else align=15;
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w= (width +align)&~align;
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h= (height+align)&~align;
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if(!(s->flags&CODEC_FLAG_EMU_EDGE)){
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w+= EDGE_WIDTH*2;
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h+= EDGE_WIDTH*2;
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}
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buf->last_pic_num= -256*256*256*64;
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for(i=0; i<3; i++){
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const int h_shift= i==0 ? 0 : h_chroma_shift;
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const int v_shift= i==0 ? 0 : v_chroma_shift;
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pic->linesize[i]= pixel_size*w>>h_shift;
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buf->base[i]= av_mallocz((pic->linesize[i]*h>>v_shift)+16); //FIXME 16
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if(buf->base[i]==NULL) return -1;
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memset(buf->base[i], 128, pic->linesize[i]*h>>v_shift);
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if(s->flags&CODEC_FLAG_EMU_EDGE)
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buf->data[i] = buf->base[i];
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else
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buf->data[i] = buf->base[i] + (pic->linesize[i]*EDGE_WIDTH>>v_shift) + (EDGE_WIDTH>>h_shift);
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}
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pic->age= 256*256*256*64;
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pic->type= FF_BUFFER_TYPE_INTERNAL;
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}
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for(i=0; i<4; i++){
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pic->base[i]= buf->base[i];
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pic->data[i]= buf->data[i];
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}
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s->internal_buffer_count++;
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return 0;
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}
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void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic){
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int i;
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InternalBuffer *buf, *last, temp;
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assert(pic->type==FF_BUFFER_TYPE_INTERNAL);
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assert(s->internal_buffer_count);
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buf = NULL; /* avoids warning */
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for(i=0; i<s->internal_buffer_count; i++){ //just 3-5 checks so is not worth to optimize
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buf= &((InternalBuffer*)s->internal_buffer)[i];
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if(buf->data[0] == pic->data[0])
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break;
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}
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assert(i < s->internal_buffer_count);
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s->internal_buffer_count--;
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last = &((InternalBuffer*)s->internal_buffer)[s->internal_buffer_count];
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temp= *buf;
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*buf= *last;
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*last= temp;
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for(i=0; i<3; i++){
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pic->data[i]=NULL;
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// pic->base[i]=NULL;
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}
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//printf("R%X\n", pic->opaque);
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}
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enum PixelFormat avcodec_default_get_format(struct AVCodecContext *s, enum PixelFormat * fmt){
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return fmt[0];
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}
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void avcodec_get_context_defaults(AVCodecContext *s){
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s->bit_rate= 800*1000;
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s->bit_rate_tolerance= s->bit_rate*10;
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s->qmin= 2;
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s->qmax= 31;
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s->mb_qmin= 2;
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s->mb_qmax= 31;
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s->rc_eq= "tex^qComp";
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s->qcompress= 0.5;
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s->max_qdiff= 3;
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s->b_quant_factor=1.25;
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s->b_quant_offset=1.25;
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s->i_quant_factor=-0.8;
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s->i_quant_offset=0.0;
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s->error_concealment= 3;
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s->error_resilience= 1;
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s->workaround_bugs= FF_BUG_AUTODETECT;
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s->frame_rate_base= 1;
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s->frame_rate = 25;
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s->gop_size= 50;
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s->me_method= ME_EPZS;
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s->get_buffer= avcodec_default_get_buffer;
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s->release_buffer= avcodec_default_release_buffer;
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s->get_format= avcodec_default_get_format;
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s->me_subpel_quality=8;
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s->intra_quant_bias= FF_DEFAULT_QUANT_BIAS;
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s->inter_quant_bias= FF_DEFAULT_QUANT_BIAS;
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}
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/**
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* allocates a AVCodecContext and set it to defaults.
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* this can be deallocated by simply calling free()
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*/
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AVCodecContext *avcodec_alloc_context(void){
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AVCodecContext *avctx= av_mallocz(sizeof(AVCodecContext));
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if(avctx==NULL) return NULL;
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avcodec_get_context_defaults(avctx);
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return avctx;
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}
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/**
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* allocates a AVPFrame and set it to defaults.
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* this can be deallocated by simply calling free()
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*/
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AVFrame *avcodec_alloc_frame(void){
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AVFrame *pic= av_mallocz(sizeof(AVFrame));
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return pic;
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}
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int avcodec_open(AVCodecContext *avctx, AVCodec *codec)
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{
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int ret;
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if(avctx->codec)
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return -1;
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avctx->codec = codec;
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avctx->codec_id = codec->id;
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avctx->frame_number = 0;
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if (codec->priv_data_size > 0) {
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avctx->priv_data = av_mallocz(codec->priv_data_size);
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if (!avctx->priv_data)
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return -ENOMEM;
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} else {
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avctx->priv_data = NULL;
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}
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ret = avctx->codec->init(avctx);
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if (ret < 0) {
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av_freep(&avctx->priv_data);
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return ret;
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}
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return 0;
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}
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int avcodec_encode_audio(AVCodecContext *avctx, uint8_t *buf, int buf_size,
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const short *samples)
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{
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int ret;
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ret = avctx->codec->encode(avctx, buf, buf_size, (void *)samples);
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avctx->frame_number++;
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return ret;
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}
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int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size,
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const AVFrame *pict)
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{
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int ret;
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ret = avctx->codec->encode(avctx, buf, buf_size, (void *)pict);
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emms_c(); //needed to avoid a emms_c() call before every return;
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avctx->frame_number++;
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return ret;
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}
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/**
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* decode a frame.
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* @param buf bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE larger then the actual read bytes
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* because some optimized bitstream readers read 32 or 64 bit at once and could read over the end
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* @param buf_size the size of the buffer in bytes
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* @param got_picture_ptr zero if no frame could be decompressed, Otherwise, it is non zero
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* @return -1 if error, otherwise return the number of
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* bytes used.
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*/
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int avcodec_decode_video(AVCodecContext *avctx, AVFrame *picture,
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int *got_picture_ptr,
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uint8_t *buf, int buf_size)
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{
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int ret;
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ret = avctx->codec->decode(avctx, picture, got_picture_ptr,
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buf, buf_size);
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emms_c(); //needed to avoid a emms_c() call before every return;
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if (*got_picture_ptr)
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avctx->frame_number++;
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return ret;
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}
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/* decode an audio frame. return -1 if error, otherwise return the
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*number of bytes used. If no frame could be decompressed,
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*frame_size_ptr is zero. Otherwise, it is the decompressed frame
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*size in BYTES. */
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int avcodec_decode_audio(AVCodecContext *avctx, int16_t *samples,
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int *frame_size_ptr,
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uint8_t *buf, int buf_size)
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{
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int ret;
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ret = avctx->codec->decode(avctx, samples, frame_size_ptr,
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buf, buf_size);
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avctx->frame_number++;
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return ret;
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}
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int avcodec_close(AVCodecContext *avctx)
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{
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if (avctx->codec->close)
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avctx->codec->close(avctx);
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av_freep(&avctx->priv_data);
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avctx->codec = NULL;
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return 0;
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}
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AVCodec *avcodec_find_encoder(enum CodecID id)
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{
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AVCodec *p;
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p = first_avcodec;
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while (p) {
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if (p->encode != NULL && p->id == id)
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return p;
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p = p->next;
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}
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return NULL;
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}
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AVCodec *avcodec_find_encoder_by_name(const char *name)
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{
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AVCodec *p;
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p = first_avcodec;
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while (p) {
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if (p->encode != NULL && strcmp(name,p->name) == 0)
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return p;
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p = p->next;
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}
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return NULL;
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}
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AVCodec *avcodec_find_decoder(enum CodecID id)
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{
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AVCodec *p;
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p = first_avcodec;
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while (p) {
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if (p->decode != NULL && p->id == id)
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return p;
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p = p->next;
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}
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return NULL;
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}
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AVCodec *avcodec_find_decoder_by_name(const char *name)
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{
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AVCodec *p;
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p = first_avcodec;
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while (p) {
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if (p->decode != NULL && strcmp(name,p->name) == 0)
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return p;
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p = p->next;
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}
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return NULL;
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}
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AVCodec *avcodec_find(enum CodecID id)
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{
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AVCodec *p;
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p = first_avcodec;
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while (p) {
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if (p->id == id)
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return p;
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p = p->next;
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}
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return NULL;
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}
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void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
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{
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const char *codec_name;
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AVCodec *p;
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char buf1[32];
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char channels_str[100];
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int bitrate;
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if (encode)
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p = avcodec_find_encoder(enc->codec_id);
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else
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p = avcodec_find_decoder(enc->codec_id);
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if (p) {
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codec_name = p->name;
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if (!encode && enc->codec_id == CODEC_ID_MP3) {
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if (enc->sub_id == 2)
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codec_name = "mp2";
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else if (enc->sub_id == 1)
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codec_name = "mp1";
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}
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} else if (enc->codec_name[0] != '\0') {
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codec_name = enc->codec_name;
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} else {
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/* output avi tags */
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if (enc->codec_type == CODEC_TYPE_VIDEO) {
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snprintf(buf1, sizeof(buf1), "%c%c%c%c",
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enc->codec_tag & 0xff,
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(enc->codec_tag >> 8) & 0xff,
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(enc->codec_tag >> 16) & 0xff,
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(enc->codec_tag >> 24) & 0xff);
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} else {
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snprintf(buf1, sizeof(buf1), "0x%04x", enc->codec_tag);
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}
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codec_name = buf1;
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}
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switch(enc->codec_type) {
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case CODEC_TYPE_VIDEO:
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snprintf(buf, buf_size,
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"Video: %s%s",
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codec_name, enc->mb_decision ? " (hq)" : "");
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if (enc->codec_id == CODEC_ID_RAWVIDEO) {
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snprintf(buf + strlen(buf), buf_size - strlen(buf),
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", %s",
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avcodec_get_pix_fmt_name(enc->pix_fmt));
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}
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if (enc->width) {
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snprintf(buf + strlen(buf), buf_size - strlen(buf),
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", %dx%d, %0.2f fps",
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enc->width, enc->height,
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(float)enc->frame_rate / enc->frame_rate_base);
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}
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if (encode) {
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snprintf(buf + strlen(buf), buf_size - strlen(buf),
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", q=%d-%d", enc->qmin, enc->qmax);
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}
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bitrate = enc->bit_rate;
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break;
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case CODEC_TYPE_AUDIO:
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snprintf(buf, buf_size,
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"Audio: %s",
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codec_name);
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switch (enc->channels) {
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case 1:
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strcpy(channels_str, "mono");
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break;
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case 2:
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strcpy(channels_str, "stereo");
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break;
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case 6:
|
|
strcpy(channels_str, "5:1");
|
|
break;
|
|
default:
|
|
sprintf(channels_str, "%d channels", enc->channels);
|
|
break;
|
|
}
|
|
if (enc->sample_rate) {
|
|
snprintf(buf + strlen(buf), buf_size - strlen(buf),
|
|
", %d Hz, %s",
|
|
enc->sample_rate,
|
|
channels_str);
|
|
}
|
|
|
|
/* for PCM codecs, compute bitrate directly */
|
|
switch(enc->codec_id) {
|
|
case CODEC_ID_PCM_S16LE:
|
|
case CODEC_ID_PCM_S16BE:
|
|
case CODEC_ID_PCM_U16LE:
|
|
case CODEC_ID_PCM_U16BE:
|
|
bitrate = enc->sample_rate * enc->channels * 16;
|
|
break;
|
|
case CODEC_ID_PCM_S8:
|
|
case CODEC_ID_PCM_U8:
|
|
case CODEC_ID_PCM_ALAW:
|
|
case CODEC_ID_PCM_MULAW:
|
|
bitrate = enc->sample_rate * enc->channels * 8;
|
|
break;
|
|
default:
|
|
bitrate = enc->bit_rate;
|
|
break;
|
|
}
|
|
break;
|
|
default:
|
|
av_abort();
|
|
}
|
|
if (encode) {
|
|
if (enc->flags & CODEC_FLAG_PASS1)
|
|
snprintf(buf + strlen(buf), buf_size - strlen(buf),
|
|
", pass 1");
|
|
if (enc->flags & CODEC_FLAG_PASS2)
|
|
snprintf(buf + strlen(buf), buf_size - strlen(buf),
|
|
", pass 2");
|
|
}
|
|
if (bitrate != 0) {
|
|
snprintf(buf + strlen(buf), buf_size - strlen(buf),
|
|
", %d kb/s", bitrate / 1000);
|
|
}
|
|
}
|
|
|
|
unsigned avcodec_version( void )
|
|
{
|
|
return LIBAVCODEC_VERSION_INT;
|
|
}
|
|
|
|
unsigned avcodec_build( void )
|
|
{
|
|
return LIBAVCODEC_BUILD;
|
|
}
|
|
|
|
/* must be called before any other functions */
|
|
void avcodec_init(void)
|
|
{
|
|
static int inited = 0;
|
|
|
|
if (inited != 0)
|
|
return;
|
|
inited = 1;
|
|
|
|
dsputil_static_init();
|
|
}
|
|
|
|
/**
|
|
* Flush buffers, should be called when seeking or when swicthing to a different stream.
|
|
*/
|
|
void avcodec_flush_buffers(AVCodecContext *avctx)
|
|
{
|
|
if(avctx->codec->flush)
|
|
avctx->codec->flush(avctx);
|
|
}
|
|
|
|
void avcodec_default_free_buffers(AVCodecContext *s){
|
|
int i, j;
|
|
|
|
if(s->internal_buffer==NULL) return;
|
|
|
|
for(i=0; i<INTERNAL_BUFFER_SIZE; i++){
|
|
InternalBuffer *buf= &((InternalBuffer*)s->internal_buffer)[i];
|
|
for(j=0; j<4; j++){
|
|
av_freep(&buf->base[j]);
|
|
buf->data[j]= NULL;
|
|
}
|
|
}
|
|
av_freep(&s->internal_buffer);
|
|
|
|
s->internal_buffer_count=0;
|
|
}
|
|
|
|
char av_get_pict_type_char(int pict_type){
|
|
switch(pict_type){
|
|
case I_TYPE: return 'I';
|
|
case P_TYPE: return 'P';
|
|
case B_TYPE: return 'B';
|
|
case S_TYPE: return 'S';
|
|
case SI_TYPE:return 'i';
|
|
case SP_TYPE:return 'p';
|
|
default: return '?';
|
|
}
|
|
}
|
|
|
|
int av_reduce(int *dst_nom, int *dst_den, int64_t nom, int64_t den, int64_t max){
|
|
int exact=1, sign=0;
|
|
int64_t gcd, larger;
|
|
|
|
assert(den != 0);
|
|
|
|
if(den < 0){
|
|
den= -den;
|
|
nom= -nom;
|
|
}
|
|
|
|
if(nom < 0){
|
|
nom= -nom;
|
|
sign= 1;
|
|
}
|
|
|
|
for(;;){ //note is executed 1 or 2 times
|
|
gcd = ff_gcd(nom, den);
|
|
nom /= gcd;
|
|
den /= gcd;
|
|
|
|
larger= FFMAX(nom, den);
|
|
|
|
if(larger > max){
|
|
int64_t div= (larger + max - 1) / max;
|
|
nom = (nom + div/2)/div;
|
|
den = (den + div/2)/div;
|
|
exact=0;
|
|
}else
|
|
break;
|
|
}
|
|
|
|
if(sign) nom= -nom;
|
|
|
|
*dst_nom = nom;
|
|
*dst_den = den;
|
|
|
|
return exact;
|
|
}
|
|
|
|
int64_t av_rescale(int64_t a, int b, int c){
|
|
uint64_t h, l;
|
|
assert(c > 0);
|
|
assert(b >=0);
|
|
|
|
if(a<0) return -av_rescale(-a, b, c);
|
|
|
|
h= a>>32;
|
|
if(h==0) return a*b/c;
|
|
|
|
l= a&0xFFFFFFFF;
|
|
l *= b;
|
|
h *= b;
|
|
|
|
l += (h%c)<<32;
|
|
|
|
return ((h/c)<<32) + l/c;
|
|
}
|