output.c

   1
   2 #include <stdint.h>
   3 #include <malloc.h>
   4 #include <libavutil/avutil.h>
   5 #include <libswscale/swscale.h>
   6 #include <png.h>
   7
   8 #include "common.h"
   9 #include "output.h"
  10
  11 typedef struct {
  12         FILE *fh;
  13         png_structp p_png;
  14         png_infop   p_info;
  15 } png_output_t;
  16
  17 int open_file_png(char *psz_filename, hnd_t *p_handle, int i_compression )
  18 {
  19         png_output_t *h = NULL;
  20         if( (h = calloc(1, sizeof(*h))) == NULL )
  21                 return -1;
  22
  23         if( !strcmp(psz_filename, "-") )
  24                 h->fh = stdout;
  25         else if( (h->fh = fopen(psz_filename, "wb")) == NULL )
  26         {
  27                 goto error;
  28         }
  29
  30         if( (h->p_png = png_create_write_struct( PNG_LIBPNG_VER_STRING, NULL, NULL, NULL )) == NULL )
  31         {
  32                 goto error;
  33         }
  34
  35         if( (h->p_info = png_create_info_struct(h->p_png)) == NULL )
  36         {
  37                 png_destroy_write_struct(&(h->p_png), (png_infopp)NULL);
  38                 goto error;
  39         }
  40
  41         png_init_io( h->p_png, h->fh );
  42
  43         png_set_compression_level( h->p_png, i_compression );
  44
  45         *p_handle = h;
  46
  47         return 0;
  48
  49 error:
  50         if( h->fh != NULL && h->fh != stdout )
  51                 fclose( h->fh );
  52         free(h);
  53
  54         return -1;
  55 }
  56
  57 int close_file_png( hnd_t handle )
  58 {
  59         int ret = 0;
  60         png_output_t *h = handle;
  61
  62         png_destroy_write_struct( &(h->p_png), &(h->p_info) );
  63
  64         if ((h->fh == NULL) || (h->fh == stdout))
  65                 return ret;
  66
  67         ret = fclose(h->fh);
  68
  69         free(h);
  70
  71         return ret;
  72 }
  73
  74 int write_image_png( hnd_t handle, picture_t *p_pic, config_t *p_config )
  75 {
  76         png_output_t *h = handle;
  77         uint8_t *out_data = malloc(p_config->i_width * p_config->i_height * 4);
  78         uint8_t **pp_rows = calloc(p_config->i_height, sizeof(*pp_rows));
  79         picture_t pic_out;
  80         struct SwsContext *p_sws;
  81         int i;
  82
  83         pic_out.img.plane[0] = out_data;
  84         pic_out.img.plane[1] = pic_out.img.plane[2] = pic_out.img.plane[3] = NULL;
  85         pic_out.img.i_stride[0] = 3*p_config->i_width;
  86         pic_out.img.i_stride[1] = pic_out.img.i_stride[2] = pic_out.img.i_stride[3] = 0;
  87
  88         p_sws = sws_getContext( p_config->i_width, p_config->i_height, PIX_FMT_YUV420P,
  89                                                         p_config->i_width, p_config->i_height, PIX_FMT_RGB24,
  90                                                         SWS_FAST_BILINEAR | SWS_ACCURATE_RND,
  91                                                         NULL, NULL, NULL );
  92
  93         sws_scale(p_sws, p_pic->img.plane, p_pic->img.i_stride, 0, p_config->i_height, pic_out.img.plane, pic_out.img.i_stride );
  94
  95         __asm__ volatile ("emms\n\t");
  96
  97
  98         png_set_IHDR( h->p_png, h->p_info, p_config->i_width, p_config->i_height,
  99                                   8, PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE,
 100                                   PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT );
 101
 102         for(i=0; i < p_config->i_height; i++)
 103                 pp_rows[i] = pic_out.img.plane[0] + i * pic_out.img.i_stride[0];
 104
 105         png_set_rows( h->p_png, h->p_info, pp_rows );
 106
 107         png_write_png( h->p_png, h->p_info, 0, NULL );
 108
 109         free(pp_rows);
 110         free(out_data);
 111
 112         return 0;
 113 }