example.c: Fix 12-bit PPM write w/ big endian CPUs
diff --git a/example.c b/example.c
index 837254c..4a82695 100644
--- a/example.c
+++ b/example.c
@@ -4,7 +4,7 @@
* This file was part of the Independent JPEG Group's software.
* Copyright (C) 1992-1996, Thomas G. Lane.
* libjpeg-turbo Modifications:
- * Copyright (C) 2017, 2019, 2022, D. R. Commander.
+ * Copyright (C) 2017, 2019, 2022-2023, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
@@ -398,6 +398,7 @@
J12SAMPARRAY buffer12 = NULL; /* 12-bit output row buffer */
int col;
int row_stride; /* physical row width in output buffer */
+ int little_endian = 1;
/* In this example we want to open the input and output files before doing
* anything else, so that the setjmp() error recovery below can assume the
@@ -494,10 +495,12 @@
* more than one scanline at a time if that's more convenient.
*/
(void)jpeg12_read_scanlines(cinfo, buffer12, 1);
- /* Swap MSB and LSB in each sample */
- for (col = 0; col < row_stride; col++)
- buffer12[0][col] = ((buffer12[0][col] & 0xFF) << 8) |
- ((buffer12[0][col] >> 8) & 0xFF);
+ if (*(char *)&little_endian == 1) {
+ /* Swap MSB and LSB in each sample */
+ for (col = 0; col < row_stride; col++)
+ buffer12[0][col] = ((buffer12[0][col] & 0xFF) << 8) |
+ ((buffer12[0][col] >> 8) & 0xFF);
+ }
fwrite(buffer12[0], 1, row_stride * sizeof(J12SAMPLE), outfile);
}
} else {
