Improve performance of non-SIMD color conversion routines and use global constants to define colorspace extension parameters
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@698 632fc199-4ca6-4c93-a231-07263d6284db
diff --git a/jccolext.c b/jccolext.c
new file mode 100644
index 0000000..acbfa23
--- /dev/null
+++ b/jccolext.c
@@ -0,0 +1,114 @@
+/*
+ * jccolext.c
+ *
+ * Copyright (C) 1991-1996, Thomas G. Lane.
+ * Copyright (C) 2009-2011, D. R. Commander.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains input colorspace conversion routines.
+ */
+
+
+/* This file is included by jccolor.c */
+
+
+/*
+ * Convert some rows of samples to the JPEG colorspace.
+ *
+ * Note that we change from the application's interleaved-pixel format
+ * to our internal noninterleaved, one-plane-per-component format.
+ * The input buffer is therefore three times as wide as the output buffer.
+ *
+ * A starting row offset is provided only for the output buffer. The caller
+ * can easily adjust the passed input_buf value to accommodate any row
+ * offset required on that side.
+ */
+
+INLINE
+LOCAL(void)
+rgb_ycc_convert_internal (j_compress_ptr cinfo,
+ JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
+ JDIMENSION output_row, int num_rows)
+{
+ my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
+ register int r, g, b;
+ register INT32 * ctab = cconvert->rgb_ycc_tab;
+ register JSAMPROW inptr;
+ register JSAMPROW outptr0, outptr1, outptr2;
+ register JDIMENSION col;
+ JDIMENSION num_cols = cinfo->image_width;
+
+ while (--num_rows >= 0) {
+ inptr = *input_buf++;
+ outptr0 = output_buf[0][output_row];
+ outptr1 = output_buf[1][output_row];
+ outptr2 = output_buf[2][output_row];
+ output_row++;
+ for (col = 0; col < num_cols; col++) {
+ r = GETJSAMPLE(inptr[RGB_RED]);
+ g = GETJSAMPLE(inptr[RGB_GREEN]);
+ b = GETJSAMPLE(inptr[RGB_BLUE]);
+ inptr += RGB_PIXELSIZE;
+ /* If the inputs are 0..MAXJSAMPLE, the outputs of these equations
+ * must be too; we do not need an explicit range-limiting operation.
+ * Hence the value being shifted is never negative, and we don't
+ * need the general RIGHT_SHIFT macro.
+ */
+ /* Y */
+ outptr0[col] = (JSAMPLE)
+ ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
+ >> SCALEBITS);
+ /* Cb */
+ outptr1[col] = (JSAMPLE)
+ ((ctab[r+R_CB_OFF] + ctab[g+G_CB_OFF] + ctab[b+B_CB_OFF])
+ >> SCALEBITS);
+ /* Cr */
+ outptr2[col] = (JSAMPLE)
+ ((ctab[r+R_CR_OFF] + ctab[g+G_CR_OFF] + ctab[b+B_CR_OFF])
+ >> SCALEBITS);
+ }
+ }
+}
+
+
+/**************** Cases other than RGB -> YCbCr **************/
+
+
+/*
+ * Convert some rows of samples to the JPEG colorspace.
+ * This version handles RGB->grayscale conversion, which is the same
+ * as the RGB->Y portion of RGB->YCbCr.
+ * We assume rgb_ycc_start has been called (we only use the Y tables).
+ */
+
+INLINE
+LOCAL(void)
+rgb_gray_convert_internal (j_compress_ptr cinfo,
+ JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
+ JDIMENSION output_row, int num_rows)
+{
+ my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
+ register int r, g, b;
+ register INT32 * ctab = cconvert->rgb_ycc_tab;
+ register JSAMPROW inptr;
+ register JSAMPROW outptr;
+ register JDIMENSION col;
+ JDIMENSION num_cols = cinfo->image_width;
+
+ while (--num_rows >= 0) {
+ inptr = *input_buf++;
+ outptr = output_buf[0][output_row];
+ output_row++;
+ for (col = 0; col < num_cols; col++) {
+ r = GETJSAMPLE(inptr[RGB_RED]);
+ g = GETJSAMPLE(inptr[RGB_GREEN]);
+ b = GETJSAMPLE(inptr[RGB_BLUE]);
+ inptr += RGB_PIXELSIZE;
+ /* Y */
+ outptr[col] = (JSAMPLE)
+ ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
+ >> SCALEBITS);
+ }
+ }
+}