diff options
author | Thomas G. Lane <tgl@netcom.com> | 1995-08-02 00:00:00 +0000 |
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committer | DRC <information@libjpeg-turbo.org> | 2015-07-29 15:31:30 -0500 |
commit | bc79e0680a45d1ca330d690dae0340c8e17ab5e3 (patch) | |
tree | a72d3996a6a70824338566ef36c2fe8acb00fba0 /example.c | |
parent | a8b67c4fbbfde9b4b4e03f2dea8f4f0b1900fc33 (diff) | |
download | libjpeg-turbo-bc79e0680a45d1ca330d690dae0340c8e17ab5e3.tar.gz |
The Independent JPEG Group's JPEG software v6
Diffstat (limited to 'example.c')
-rw-r--r-- | example.c | 15 |
1 files changed, 13 insertions, 2 deletions
@@ -154,6 +154,10 @@ write_JPEG_file (char * filename, int quality) row_stride = image_width * 3; /* JSAMPLEs per row in image_buffer */ while (cinfo.next_scanline < cinfo.image_height) { + /* jpeg_write_scanlines expects an array of pointers to scanlines. + * Here the array is only one element long, but you could pass + * more than one scanline at a time if that's more convenient. + */ row_pointer[0] = & image_buffer[cinfo.next_scanline * row_stride]; (void) jpeg_write_scanlines(&cinfo, row_pointer, 1); } @@ -188,7 +192,7 @@ write_JPEG_file (char * filename, int quality) * (If you don't know what that's for, you don't need it.) * * If the compressor requires full-image buffers (for entropy-coding - * optimization or a noninterleaved JPEG file), it will create temporary + * optimization or a multi-scan JPEG file), it will create temporary * files for anything that doesn't fit within the maximum-memory setting. * (Note that temp files are NOT needed if you use the default parameters.) * On some systems you may need to set up a signal handler to ensure that @@ -342,7 +346,10 @@ read_JPEG_file (char * filename) /* Step 5: Start decompressor */ - jpeg_start_decompress(&cinfo); + (void) jpeg_start_decompress(&cinfo); + /* We can ignore the return value since suspension is not possible + * with the stdio data source. + */ /* We may need to do some setup of our own at this point before reading * the data. After jpeg_start_decompress() we have the correct scaled @@ -363,6 +370,10 @@ read_JPEG_file (char * filename) * loop counter, so that we don't have to keep track ourselves. */ while (cinfo.output_scanline < cinfo.output_height) { + /* jpeg_read_scanlines expects an array of pointers to scanlines. + * Here the array is only one element long, but you could ask for + * more than one scanline at a time if that's more convenient. + */ (void) jpeg_read_scanlines(&cinfo, buffer, 1); /* Assume put_scanline_someplace wants a pointer and sample count. */ put_scanline_someplace(buffer[0], row_stride); |