mpv/libmpcodecs/vd_mpng.c

162 lines
4.2 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include "config.h"
#include "mp_msg.h"
#include <png.h>
#include "libavutil/common.h"
#include "mpbswap.h"
#include "libvo/fastmemcpy.h"
#include "vd_internal.h"
static const vd_info_t info = {
"PNG Images decoder",
"mpng",
"A'rpi",
".so, based on mpng.c",
"uses libpng, 8bpp modes not supported yet"
};
LIBVD_EXTERN(mpng)
static unsigned int out_fmt=0;
static int last_w=-1;
static int last_h=-1;
static int last_c=-1;
// to set/get/query special features/parameters
static int control(sh_video_t *sh,int cmd,void* arg,...){
switch (cmd)
{
case VDCTRL_QUERY_FORMAT:
if (*((int *) arg) == out_fmt) return CONTROL_TRUE;
return CONTROL_FALSE;
}
return CONTROL_UNKNOWN;
}
// init driver
static int init(sh_video_t *sh){
last_w=-1;
return 1;
}
// uninit driver
static void uninit(sh_video_t *sh){
}
//mp_image_t* mpcodecs_get_image(sh_video_t *sh, int mp_imgtype, int mp_imgflag, int w, int h);
static int pngPointer;
static int pngLength;
static void pngReadFN( png_structp pngstr,png_bytep buffer,png_size_t size )
{
char * p = pngstr->io_ptr;
if(size>pngLength-pngPointer && pngLength>=pngPointer) size=pngLength-pngPointer;
fast_memcpy( buffer,(char *)&p[pngPointer],size );
pngPointer+=size;
}
// decode a frame
static mp_image_t* decode(sh_video_t *sh,void* data,int len,int flags){
png_structp png;
png_infop info;
png_infop endinfo;
// png_bytep data;
png_bytep * row_p;
png_uint_32 png_width=0,png_height=0;
int depth,color;
png_uint_32 i;
mp_image_t* mpi;
int cols;
png_colorp pal;
unsigned char *p;
if(len<=0) return NULL; // skipped frame
png=png_create_read_struct( PNG_LIBPNG_VER_STRING,NULL,NULL,NULL );
info=png_create_info_struct( png );
endinfo=png_create_info_struct( png );
pngPointer=8;
pngLength=len;
png_set_read_fn( png,data,pngReadFN );
png_set_strip_16( png );
png_set_sig_bytes( png,8 );
png_read_info( png,info );
png_get_IHDR( png,info,&png_width,&png_height,&depth,&color,NULL,NULL,NULL );
png_set_bgr( png );
switch( info->color_type ) {
case PNG_COLOR_TYPE_GRAY_ALPHA:
mp_msg( MSGT_DECVIDEO,MSGL_INFO,"Sorry gray scaled png with alpha channel not supported at moment.\n" );
break;
case PNG_COLOR_TYPE_GRAY:
out_fmt=IMGFMT_Y800;
break;
case PNG_COLOR_TYPE_PALETTE:
out_fmt=IMGFMT_BGR8;
break;
case PNG_COLOR_TYPE_RGB_ALPHA:
out_fmt=IMGFMT_BGR32;
break;
case PNG_COLOR_TYPE_RGB:
out_fmt=IMGFMT_BGR24;
break;
default:
mp_msg( MSGT_DECVIDEO,MSGL_INFO,"Sorry, unsupported PNG colorspace: %d.\n" ,info->color_type);
}
// (re)init libvo if image parameters changed (width/height/colorspace)
if(last_w!=png_width || last_h!=png_height || last_c!=out_fmt){
last_w=png_width; last_h=png_height; last_c=out_fmt;
if(!out_fmt) return NULL;
if(!mpcodecs_config_vo(sh,png_width,png_height,out_fmt)) return NULL;
}
#if 0
switch( info->color_type )
{
case PNG_COLOR_TYPE_GRAY_ALPHA: printf( "[png] used GrayA -> stripping alpha channel\n" ); break;
case PNG_COLOR_TYPE_GRAY: printf( "[png] used Gray -> rgb\n" ); break;
case PNG_COLOR_TYPE_PALETTE: printf( "[png] used palette -> rgb\n" ); break;
case PNG_COLOR_TYPE_RGB_ALPHA: printf( "[png] used RGBA -> stripping alpha channel\n" ); break;
case PNG_COLOR_TYPE_RGB: printf( "[png] read rgb datas.\n" ); break;
}
#endif
mpi=mpcodecs_get_image(sh, MP_IMGTYPE_TEMP, MP_IMGFLAG_ACCEPT_STRIDE,
png_width,png_height);
if(!mpi) return NULL;
// Let's DECODE!
row_p=malloc( sizeof( png_bytep ) * png_height );
//png_get_rowbytes( png,info )
for ( i=0; i < png_height; i++ ) row_p[i]=mpi->planes[0] + mpi->stride[0]*i;
png_read_image( png,row_p );
free( row_p );
if (out_fmt==IMGFMT_BGR8) {
png_get_PLTE( png,info,&pal,&cols );
mpi->planes[1] = (char*)realloc(mpi->planes[1], 4*cols);
p = mpi->planes[1];
for (i = 0; i < cols; i++) {
*p++ = pal[i].blue;
*p++ = pal[i].green;
*p++ = pal[i].red;
*p++ = 0;
}
}
png_read_end( png,endinfo );
png_destroy_read_struct( &png,&info,&endinfo );
return mpi;
}