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Diffstat (limited to 'src/libjpeg/jcsample.c')
-rw-r--r--src/libjpeg/jcsample.c94
1 files changed, 60 insertions, 34 deletions
diff --git a/src/libjpeg/jcsample.c b/src/libjpeg/jcsample.c
index 212ec87..4d36f85 100644
--- a/src/libjpeg/jcsample.c
+++ b/src/libjpeg/jcsample.c
@@ -62,6 +62,15 @@ typedef struct {
/* Downsampling method pointers, one per component */
downsample1_ptr methods[MAX_COMPONENTS];
+
+ /* Height of an output row group for each component. */
+ int rowgroup_height[MAX_COMPONENTS];
+
+ /* These arrays save pixel expansion factors so that int_downsample need not
+ * recompute them each time. They are unused for other downsampling methods.
+ */
+ UINT8 h_expand[MAX_COMPONENTS];
+ UINT8 v_expand[MAX_COMPONENTS];
} my_downsampler;
typedef my_downsampler * my_downsample_ptr;
@@ -123,7 +132,8 @@ sep_downsample (j_compress_ptr cinfo,
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
in_ptr = input_buf[ci] + in_row_index;
- out_ptr = output_buf[ci] + (out_row_group_index * compptr->v_samp_factor);
+ out_ptr = output_buf[ci] +
+ (out_row_group_index * downsample->rowgroup_height[ci]);
(*downsample->methods[ci]) (cinfo, compptr, in_ptr, out_ptr);
}
}
@@ -140,14 +150,15 @@ METHODDEF(void)
int_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
+ my_downsample_ptr downsample = (my_downsample_ptr) cinfo->downsample;
int inrow, outrow, h_expand, v_expand, numpix, numpix2, h, v;
JDIMENSION outcol, outcol_h; /* outcol_h == outcol*h_expand */
- JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
+ JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
JSAMPROW inptr, outptr;
INT32 outvalue;
- h_expand = cinfo->max_h_samp_factor / compptr->h_samp_factor;
- v_expand = cinfo->max_v_samp_factor / compptr->v_samp_factor;
+ h_expand = downsample->h_expand[compptr->component_index];
+ v_expand = downsample->v_expand[compptr->component_index];
numpix = h_expand * v_expand;
numpix2 = numpix/2;
@@ -158,8 +169,8 @@ int_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
expand_right_edge(input_data, cinfo->max_v_samp_factor,
cinfo->image_width, output_cols * h_expand);
- inrow = 0;
- for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
+ inrow = outrow = 0;
+ while (inrow < cinfo->max_v_samp_factor) {
outptr = output_data[outrow];
for (outcol = 0, outcol_h = 0; outcol < output_cols;
outcol++, outcol_h += h_expand) {
@@ -173,6 +184,7 @@ int_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
*outptr++ = (JSAMPLE) ((outvalue + numpix2) / numpix);
}
inrow += v_expand;
+ outrow++;
}
}
@@ -191,8 +203,8 @@ fullsize_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
jcopy_sample_rows(input_data, 0, output_data, 0,
cinfo->max_v_samp_factor, cinfo->image_width);
/* Edge-expand */
- expand_right_edge(output_data, cinfo->max_v_samp_factor,
- cinfo->image_width, compptr->width_in_blocks * DCTSIZE);
+ expand_right_edge(output_data, cinfo->max_v_samp_factor, cinfo->image_width,
+ compptr->width_in_blocks * compptr->DCT_h_scaled_size);
}
@@ -212,9 +224,9 @@ METHODDEF(void)
h2v1_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
- int outrow;
+ int inrow;
JDIMENSION outcol;
- JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
+ JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
register JSAMPROW inptr, outptr;
register int bias;
@@ -225,9 +237,9 @@ h2v1_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
expand_right_edge(input_data, cinfo->max_v_samp_factor,
cinfo->image_width, output_cols * 2);
- for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
- outptr = output_data[outrow];
- inptr = input_data[outrow];
+ for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) {
+ outptr = output_data[inrow];
+ inptr = input_data[inrow];
bias = 0; /* bias = 0,1,0,1,... for successive samples */
for (outcol = 0; outcol < output_cols; outcol++) {
*outptr++ = (JSAMPLE) ((GETJSAMPLE(*inptr) + GETJSAMPLE(inptr[1])
@@ -251,7 +263,7 @@ h2v2_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
{
int inrow, outrow;
JDIMENSION outcol;
- JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
+ JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
register JSAMPROW inptr0, inptr1, outptr;
register int bias;
@@ -262,8 +274,8 @@ h2v2_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
expand_right_edge(input_data, cinfo->max_v_samp_factor,
cinfo->image_width, output_cols * 2);
- inrow = 0;
- for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
+ inrow = outrow = 0;
+ while (inrow < cinfo->max_v_samp_factor) {
outptr = output_data[outrow];
inptr0 = input_data[inrow];
inptr1 = input_data[inrow+1];
@@ -276,6 +288,7 @@ h2v2_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
inptr0 += 2; inptr1 += 2;
}
inrow += 2;
+ outrow++;
}
}
@@ -294,7 +307,7 @@ h2v2_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
{
int inrow, outrow;
JDIMENSION colctr;
- JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
+ JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
register JSAMPROW inptr0, inptr1, above_ptr, below_ptr, outptr;
INT32 membersum, neighsum, memberscale, neighscale;
@@ -321,8 +334,8 @@ h2v2_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
memberscale = 16384 - cinfo->smoothing_factor * 80; /* scaled (1-5*SF)/4 */
neighscale = cinfo->smoothing_factor * 16; /* scaled SF/4 */
- inrow = 0;
- for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
+ inrow = outrow = 0;
+ while (inrow < cinfo->max_v_samp_factor) {
outptr = output_data[outrow];
inptr0 = input_data[inrow];
inptr1 = input_data[inrow+1];
@@ -378,6 +391,7 @@ h2v2_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info * compptr,
*outptr = (JSAMPLE) ((membersum + 32768) >> 16);
inrow += 2;
+ outrow++;
}
}
@@ -392,9 +406,9 @@ METHODDEF(void)
fullsize_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info *compptr,
JSAMPARRAY input_data, JSAMPARRAY output_data)
{
- int outrow;
+ int inrow;
JDIMENSION colctr;
- JDIMENSION output_cols = compptr->width_in_blocks * DCTSIZE;
+ JDIMENSION output_cols = compptr->width_in_blocks * compptr->DCT_h_scaled_size;
register JSAMPROW inptr, above_ptr, below_ptr, outptr;
INT32 membersum, neighsum, memberscale, neighscale;
int colsum, lastcolsum, nextcolsum;
@@ -415,11 +429,11 @@ fullsize_smooth_downsample (j_compress_ptr cinfo, jpeg_component_info *compptr,
memberscale = 65536L - cinfo->smoothing_factor * 512L; /* scaled 1-8*SF */
neighscale = cinfo->smoothing_factor * 64; /* scaled SF */
- for (outrow = 0; outrow < compptr->v_samp_factor; outrow++) {
- outptr = output_data[outrow];
- inptr = input_data[outrow];
- above_ptr = input_data[outrow-1];
- below_ptr = input_data[outrow+1];
+ for (inrow = 0; inrow < cinfo->max_v_samp_factor; inrow++) {
+ outptr = output_data[inrow];
+ inptr = input_data[inrow];
+ above_ptr = input_data[inrow-1];
+ below_ptr = input_data[inrow+1];
/* Special case for first column */
colsum = GETJSAMPLE(*above_ptr++) + GETJSAMPLE(*below_ptr++) +
@@ -467,6 +481,7 @@ jinit_downsampler (j_compress_ptr cinfo)
int ci;
jpeg_component_info * compptr;
boolean smoothok = TRUE;
+ int h_in_group, v_in_group, h_out_group, v_out_group;
downsample = (my_downsample_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
@@ -482,8 +497,17 @@ jinit_downsampler (j_compress_ptr cinfo)
/* Verify we can handle the sampling factors, and set up method pointers */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
- if (compptr->h_samp_factor == cinfo->max_h_samp_factor &&
- compptr->v_samp_factor == cinfo->max_v_samp_factor) {
+ /* Compute size of an "output group" for DCT scaling. This many samples
+ * are to be converted from max_h_samp_factor * max_v_samp_factor pixels.
+ */
+ h_out_group = (compptr->h_samp_factor * compptr->DCT_h_scaled_size) /
+ cinfo->min_DCT_h_scaled_size;
+ v_out_group = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) /
+ cinfo->min_DCT_v_scaled_size;
+ h_in_group = cinfo->max_h_samp_factor;
+ v_in_group = cinfo->max_v_samp_factor;
+ downsample->rowgroup_height[ci] = v_out_group; /* save for use later */
+ if (h_in_group == h_out_group && v_in_group == v_out_group) {
#ifdef INPUT_SMOOTHING_SUPPORTED
if (cinfo->smoothing_factor) {
downsample->methods[ci] = fullsize_smooth_downsample;
@@ -491,12 +515,12 @@ jinit_downsampler (j_compress_ptr cinfo)
} else
#endif
downsample->methods[ci] = fullsize_downsample;
- } else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor &&
- compptr->v_samp_factor == cinfo->max_v_samp_factor) {
+ } else if (h_in_group == h_out_group * 2 &&
+ v_in_group == v_out_group) {
smoothok = FALSE;
downsample->methods[ci] = h2v1_downsample;
- } else if (compptr->h_samp_factor * 2 == cinfo->max_h_samp_factor &&
- compptr->v_samp_factor * 2 == cinfo->max_v_samp_factor) {
+ } else if (h_in_group == h_out_group * 2 &&
+ v_in_group == v_out_group * 2) {
#ifdef INPUT_SMOOTHING_SUPPORTED
if (cinfo->smoothing_factor) {
downsample->methods[ci] = h2v2_smooth_downsample;
@@ -504,10 +528,12 @@ jinit_downsampler (j_compress_ptr cinfo)
} else
#endif
downsample->methods[ci] = h2v2_downsample;
- } else if ((cinfo->max_h_samp_factor % compptr->h_samp_factor) == 0 &&
- (cinfo->max_v_samp_factor % compptr->v_samp_factor) == 0) {
+ } else if ((h_in_group % h_out_group) == 0 &&
+ (v_in_group % v_out_group) == 0) {
smoothok = FALSE;
downsample->methods[ci] = int_downsample;
+ downsample->h_expand[ci] = (UINT8) (h_in_group / h_out_group);
+ downsample->v_expand[ci] = (UINT8) (v_in_group / v_out_group);
} else
ERREXIT(cinfo, JERR_FRACT_SAMPLE_NOTIMPL);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-22 03:12:58 +0000