| 1 | #include <stdio.h> |
| 2 | #include <string.h> |
| 3 | #include <png.h> |
| 4 | |
| 5 | void readpng(unsigned short *dest, const char *fname) |
| 6 | { |
| 7 | FILE *fp; |
| 8 | png_structp png_ptr = NULL; |
| 9 | png_infop info_ptr = NULL; |
| 10 | png_bytepp row_ptr = NULL; |
| 11 | int height, width, h; |
| 12 | |
| 13 | if (dest == NULL || fname == NULL) |
| 14 | { |
| 15 | return; |
| 16 | } |
| 17 | |
| 18 | fp = fopen(fname, "rb"); |
| 19 | if (fp == NULL) |
| 20 | { |
| 21 | printf(__FILE__ ": failed to open: %s\n", fname); |
| 22 | return; |
| 23 | } |
| 24 | |
| 25 | png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); |
| 26 | if (!png_ptr) |
| 27 | { |
| 28 | printf(__FILE__ ": png_create_read_struct() failed\n"); |
| 29 | fclose(fp); |
| 30 | return; |
| 31 | } |
| 32 | |
| 33 | info_ptr = png_create_info_struct(png_ptr); |
| 34 | if (!info_ptr) |
| 35 | { |
| 36 | printf(__FILE__ ": png_create_info_struct() failed\n"); |
| 37 | goto done; |
| 38 | } |
| 39 | |
| 40 | // Start reading |
| 41 | png_init_io(png_ptr, fp); |
| 42 | png_read_png(png_ptr, info_ptr, PNG_TRANSFORM_STRIP_16 | PNG_TRANSFORM_STRIP_ALPHA | PNG_TRANSFORM_PACKING, NULL); |
| 43 | row_ptr = png_get_rows(png_ptr, info_ptr); |
| 44 | if (row_ptr == NULL) |
| 45 | { |
| 46 | printf(__FILE__ ": png_get_rows() failed\n"); |
| 47 | goto done; |
| 48 | } |
| 49 | |
| 50 | height = info_ptr->height; |
| 51 | if (height > 240) height = 240; |
| 52 | width = info_ptr->width; |
| 53 | if (width > 320) width = 320; |
| 54 | |
| 55 | for (h = 0; h < height; h++) |
| 56 | { |
| 57 | unsigned char *src = row_ptr[h]; |
| 58 | int len = width; |
| 59 | while (len--) |
| 60 | { |
| 61 | *dest++ = ((src[0]&0xf8)<<8) | ((src[1]&0xf8)<<3) | (src[2] >> 3); |
| 62 | src += 3; |
| 63 | } |
| 64 | dest += 320 - width; |
| 65 | } |
| 66 | |
| 67 | |
| 68 | done: |
| 69 | png_destroy_read_struct(&png_ptr, info_ptr ? &info_ptr : NULL, (png_infopp)NULL); |
| 70 | fclose(fp); |
| 71 | } |
| 72 | |