wrlib/load_webp.c

   1 /* load_webp.c - load WEBP image from file
   2  *
   3  * Raster graphics library
   4  *
   5  * Copyright (c) 2014 Window Maker Team
   6  *
   7  *  This library is free software; you can redistribute it and/or
   8  *  modify it under the terms of the GNU Library General Public
   9  *  License as published by the Free Software Foundation; either
  10  *  version 2 of the License, or (at your option) any later version.
  11  *
  12  *  This library is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  *  Library General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU Library General Public
  18  *  License along with this library; if not, write to the Free
  19  *  Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  20  *  MA 02110-1301, USA.
  21  */
  22
  23 #include "config.h"
  24
  25 #include <stdlib.h>
  26 #include <stdio.h>
  27 #include <string.h>
  28
  29 #include <webp/decode.h>
  30
  31 #include "wraster.h"
  32 #include "imgformat.h"
  33
  34
  35 RImage *RLoadWEBP(const char *file_name)
  36 {
  37         FILE *file;
  38         RImage *image = NULL;
  39         char buffer[20];
  40         int raw_data_size;
  41         int r;
  42         uint8_t *raw_data;
  43         WebPBitstreamFeatures features;
  44         uint8_t *ret = NULL;
  45
  46         file = fopen(file_name, "rb");
  47         if (!file) {
  48                 RErrorCode = RERR_OPEN;
  49                 return NULL;
  50         }
  51
  52         if (!fread(buffer, sizeof(buffer), 1, file)) {
  53                 RErrorCode = RERR_BADIMAGEFILE;
  54                 fclose(file);
  55                 return NULL;
  56         }
  57
  58         if (!(buffer[ 0] == 'R' && buffer[ 1] == 'I' && buffer[ 2] == 'F' && buffer[ 3] == 'F' &&
  59               buffer[ 8] == 'W' && buffer[ 9] == 'E' && buffer[10] == 'B' && buffer[11] == 'P' &&
  60               buffer[12] == 'V' && buffer[13] == 'P' && buffer[14] == '8' &&
  61 #if WEBP_DECODER_ABI_VERSION < 0x0003   /* old versions don't support WEBPVP8X and WEBPVP8L */
  62               buffer[15] == ' ')) {
  63 #else
  64               (buffer[15] == ' ' || buffer[15] == 'X' || buffer[15] == 'L'))) {
  65 #endif
  66                 RErrorCode = RERR_BADFORMAT;
  67                 fclose(file);
  68                 return NULL;
  69         }
  70
  71         fseek(file, 0L, SEEK_END);
  72         raw_data_size = ftell(file);
  73
  74         if (raw_data_size <= 0) {
  75                 fprintf(stderr, "wrlib: Failed to find the WEBP file size for \"%s\"\n", file_name);
  76                 RErrorCode = RERR_BADIMAGEFILE;
  77                 fclose(file);
  78                 return NULL;
  79         }
  80
  81         raw_data = (uint8_t *) malloc(raw_data_size);
  82
  83         if (!raw_data) {
  84                 RErrorCode = RERR_NOMEMORY;
  85                 fclose(file);
  86                 return NULL;
  87         }
  88
  89         fseek(file, 0L, SEEK_SET);
  90         r = fread(raw_data, 1, raw_data_size, file);
  91         fclose(file);
  92
  93         if (r != raw_data_size) {
  94                 RErrorCode = RERR_READ;
  95                 free(raw_data);
  96                 return NULL;
  97         }
  98
  99         if (WebPGetFeatures(raw_data, raw_data_size, &features) != VP8_STATUS_OK) {
 100                 fprintf(stderr, "wrlib: WebPGetFeatures has failed on \"%s\"\n", file_name);
 101                 RErrorCode = RERR_BADIMAGEFILE;
 102                 free(raw_data);
 103                 return NULL;
 104         }
 105
 106         if (features.has_alpha) {
 107                 image = RCreateImage(features.width, features.height, True);
 108                 if (!image) {
 109                         RErrorCode = RERR_NOMEMORY;
 110                         free(raw_data);
 111                         return NULL;
 112                 }
 113                 ret = WebPDecodeRGBAInto(raw_data, raw_data_size, image->data,
 114                                          features.width * features.height * 4,
 115                                          features.width * 4);
 116         } else {
 117                 image = RCreateImage(features.width, features.height, False);
 118                 if (!image) {
 119                         RErrorCode = RERR_NOMEMORY;
 120                         free(raw_data);
 121                         return NULL;
 122                 }
 123                 ret = WebPDecodeRGBInto(raw_data, raw_data_size, image->data,
 124                                         features.width * features.height * 3,
 125                                         features.width * 3);
 126         }
 127
 128         free(raw_data);
 129
 130         if (!ret) {
 131                 fprintf(stderr, "wrlib: Failed to decode WEBP from file \"%s\"\n", file_name);
 132                 RErrorCode = RERR_BADIMAGEFILE;
 133                 RReleaseImage(image);
 134                 return NULL;
 135         }
 136
 137         return image;
 138 }