aboutsummaryrefslogtreecommitdiffhomepage
path: root/libmpcodecs/vd_mpng.c
blob: cab4cf66d40bc6288fa105e3acf814fcb314d318 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
#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;
}