diff options
| -rw-r--r-- | ff2jpg.c | 6 | ||||
| -rw-r--r-- | ff2ppm.c | 6 |
2 files changed, 8 insertions, 4 deletions
@@ -106,9 +106,11 @@ main(int argc, char *argv[]) for (j = 0, k = 0; j < rowlen; j += 4, k += 3) { a = ntohs(row[j + 3]); for (l = 0; l < 3; l++) { + /* alpha blending and 8-bit-reduction */ rowout[k + l] = (a * ntohs(row[j + l]) + - (65535 - a) * mask[l]) / - (257 * 65535); + (UINT16_MAX - a) * mask[l]) / + (UINT16_MAX * + (UINT16_MAX / UINT8_MAX)); } } jpeg_write_scanlines(&jcomp, &rowout, 1); @@ -66,9 +66,11 @@ main(int argc, char *argv[]) for (j = 0, k = 0; j < rowlen; j += 4, k += 3) { a = ntohs(row[j + 3]); for (l = 0; l < 3; l++) { + /* alpha blending and 8-bit-reduction */ rowout[k + l] = (a * ntohs(row[j + l]) + - (65535 - a) * mask[l]) / - (257 * 65535); + (UINT16_MAX - a) * mask[l]) / + (UINT16_MAX * + (UINT16_MAX / UINT8_MAX)); } } if (fwrite(rowout, sizeof(uint8_t), rowoutlen, stdout) != rowoutlen) { |