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Merge changes I25711dd5,I43188fab
* changes: Fix assertions in WebPRescalerExportRow() Add descriptions of default configuration in help info.
This commit is contained in:
Pascal Massimino
Gerrit Code Review
commit
9d4f209f80
23
README
23
README
@ -220,8 +220,9 @@ assumed to be a PNG, JPEG, TIFF or WebP file.
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Options:
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-h / -help ............. short help
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-H / -longhelp ......... long help
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-q <float> ............. quality factor (0:small..100:big)
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-alpha_q <int> ......... transparency-compression quality (0..100)
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-q <float> ............. quality factor (0:small..100:big), default=75
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-alpha_q <int> ......... transparency-compression quality (0..100),
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default=100
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-preset <string> ....... preset setting, one of:
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default, photo, picture,
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drawing, icon, text
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@ -229,15 +230,15 @@ Options:
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-z <int> ............... activates lossless preset with given
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level in [0:fast, ..., 9:slowest]
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-m <int> ............... compression method (0=fast, 6=slowest)
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-segments <int> ........ number of segments to use (1..4)
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-m <int> ............... compression method (0=fast, 6=slowest), default=4
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-segments <int> ........ number of segments to use (1..4), default=4
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-size <int> ............ target size (in bytes)
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-psnr <float> .......... target PSNR (in dB. typically: 42)
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-s <int> <int> ......... input size (width x height) for YUV
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-sns <int> ............. spatial noise shaping (0:off, 100:max)
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-f <int> ............... filter strength (0=off..100)
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-sharpness <int> ....... filter sharpness (0:most .. 7:least sharp)
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-sns <int> ............. spatial noise shaping (0:off, 100:max), default=50
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-f <int> ............... filter strength (0=off..100), default=60
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-sharpness <int> ....... filter sharpness (0:most .. 7:least sharp), default=0
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-strong ................ use strong filter instead of simple (default)
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-nostrong .............. use simple filter instead of strong
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-partition_limit <int> . limit quality to fit the 512k limit on
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@ -252,18 +253,18 @@ Options:
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-print_ssim ............ prints averaged SSIM distortion
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-print_lsim ............ prints local-similarity distortion
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-d <file.pgm> .......... dump the compressed output (PGM file)
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-alpha_method <int> .... transparency-compression method (0..1)
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-alpha_method <int> .... transparency-compression method (0..1), default=1
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-alpha_filter <string> . predictive filtering for alpha plane,
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one of: none, fast (default) or best
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-exact ................. preserve RGB values in transparent area
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-exact ................. preserve RGB values in transparent area, default=off
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-blend_alpha <hex> ..... blend colors against background color
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expressed as RGB values written in
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hexadecimal, e.g. 0xc0e0d0 for red=0xc0
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green=0xe0 and blue=0xd0
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-noalpha ............... discard any transparency information
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-lossless .............. encode image losslessly
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-lossless .............. encode image losslessly, default=off
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-near_lossless <int> ... use near-lossless image
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preprocessing (0..100=off)
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preprocessing (0..100=off), default=100
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-hint <string> ......... specify image characteristics hint,
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one of: photo, picture or graph
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@ -521,9 +521,10 @@ static void HelpLong(void) {
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printf("\nOptions:\n");
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printf(" -h / -help ............. short help\n");
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printf(" -H / -longhelp ......... long help\n");
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printf(" -q <float> ............. quality factor (0:small..100:big)\n");
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printf(" -alpha_q <int> ......... transparency-compression quality "
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"(0..100)\n");
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printf(" -q <float> ............. quality factor (0:small..100:big), "
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"default=75\n");
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printf(" -alpha_q <int> ......... transparency-compression quality (0..100),"
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"\n default=100\n");
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printf(" -preset <string> ....... preset setting, one of:\n");
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printf(" default, photo, picture,\n");
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printf(" drawing, icon, text\n");
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@ -531,16 +532,20 @@ static void HelpLong(void) {
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printf(" -z <int> ............... activates lossless preset with given\n"
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" level in [0:fast, ..., 9:slowest]\n");
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printf("\n");
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printf(" -m <int> ............... compression method (0=fast, 6=slowest)\n");
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printf(" -segments <int> ........ number of segments to use (1..4)\n");
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printf(" -m <int> ............... compression method (0=fast, 6=slowest), "
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"default=4\n");
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printf(" -segments <int> ........ number of segments to use (1..4), "
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"default=4\n");
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printf(" -size <int> ............ target size (in bytes)\n");
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printf(" -psnr <float> .......... target PSNR (in dB. typically: 42)\n");
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printf("\n");
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printf(" -s <int> <int> ......... input size (width x height) for YUV\n");
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printf(" -sns <int> ............. spatial noise shaping (0:off, 100:max)\n");
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printf(" -f <int> ............... filter strength (0=off..100)\n");
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printf(" -sns <int> ............. spatial noise shaping (0:off, 100:max), "
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"default=50\n");
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printf(" -f <int> ............... filter strength (0=off..100), "
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"default=60\n");
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printf(" -sharpness <int> ....... "
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"filter sharpness (0:most .. 7:least sharp)\n");
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"filter sharpness (0:most .. 7:least sharp), default=0\n");
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printf(" -strong ................ use strong filter instead "
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"of simple (default)\n");
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printf(" -nostrong .............. use simple filter instead of strong\n");
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@ -557,19 +562,21 @@ static void HelpLong(void) {
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printf(" -print_ssim ............ prints averaged SSIM distortion\n");
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printf(" -print_lsim ............ prints local-similarity distortion\n");
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printf(" -d <file.pgm> .......... dump the compressed output (PGM file)\n");
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printf(" -alpha_method <int> .... transparency-compression method (0..1)\n");
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printf(" -alpha_method <int> .... transparency-compression method (0..1), "
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"default=1\n");
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printf(" -alpha_filter <string> . predictive filtering for alpha plane,\n");
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printf(" one of: none, fast (default) or best\n");
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printf(" -exact ................. preserve RGB values in transparent area"
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"\n");
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printf(" -exact ................. preserve RGB values in transparent area, "
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"default=off\n");
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printf(" -blend_alpha <hex> ..... blend colors against background color\n"
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" expressed as RGB values written in\n"
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" hexadecimal, e.g. 0xc0e0d0 for red=0xc0\n"
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" green=0xe0 and blue=0xd0\n");
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printf(" -noalpha ............... discard any transparency information\n");
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printf(" -lossless .............. encode image losslessly\n");
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printf(" -lossless .............. encode image losslessly, default=off\n");
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printf(" -near_lossless <int> ... use near-lossless image\n"
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" preprocessing (0..100=off)\n");
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" preprocessing (0..100=off), "
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"default=100\n");
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#ifdef WEBP_EXPERIMENTAL_FEATURES
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printf(" -delta_palettization ... use delta palettization\n");
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#endif // WEBP_EXPERIMENTAL_FEATURES
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@ -1,5 +1,5 @@
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.\" Hey, EMACS: -*- nroff -*-
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.TH CWEBP 1 "June 23, 2016"
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.TH CWEBP 1 "August 05, 2016"
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.SH NAME
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cwebp \- compress an image file to a WebP file
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.SH SYNOPSIS
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@ -171,7 +171,7 @@ Specify the amplitude of the spatial noise shaping. Spatial noise shaping
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(or \fBsns\fP for short) refers to a general collection of built\-in algorithms
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used to decide which area of the picture should use relatively less bits,
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and where else to better transfer these bits. The possible range goes from
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0 (algorithm is off) to 100 (the maximal effect). The default value is 80.
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0 (algorithm is off) to 100 (the maximal effect). The default value is 50.
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.TP
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.BI \-segments " int
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Change the number of partitions to use during the segmentation of the
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@ -173,10 +173,10 @@ void WebPRescalerExportRow(WebPRescaler* const wrk) {
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WebPRescalerExportRowExpand(wrk);
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} else if (wrk->fxy_scale) {
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WebPRescalerExportRowShrink(wrk);
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} else { // very special case for src = dst = 1x1
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} else { // special case
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int i;
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assert(wrk->src_height == wrk->dst_height && wrk->x_add == 1);
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assert(wrk->src_width == 1 && wrk->dst_width <= 2);
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assert(wrk->src_height == 1 && wrk->dst_height == 1);
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for (i = 0; i < wrk->num_channels * wrk->dst_width; ++i) {
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wrk->dst[i] = wrk->irow[i];
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wrk->irow[i] = 0;
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@ -48,11 +48,15 @@ void WebPRescalerInit(WebPRescaler* const wrk, int src_width, int src_height,
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wrk->y_sub = wrk->y_expand ? y_sub - 1 : y_sub;
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wrk->y_accum = wrk->y_expand ? wrk->y_sub : wrk->y_add;
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if (!wrk->y_expand) {
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// this is WEBP_RESCALER_FRAC(dst_height, x_add * y_add) without the cast.
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// This is WEBP_RESCALER_FRAC(dst_height, x_add * y_add) without the cast.
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// Its value is <= WEBP_RESCALER_ONE, because dst_height <= wrk->y_add, and
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// wrk->x_add >= 1;
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const uint64_t ratio =
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(uint64_t)dst_height * WEBP_RESCALER_ONE / (wrk->x_add * wrk->y_add);
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if (ratio != (uint32_t)ratio) {
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// We can't represent the ratio with the current fixed-point precision.
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// When ratio == WEBP_RESCALER_ONE, we can't represent the ratio with the
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// current fixed-point precision. This happens when src_height ==
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// wrk->y_add (which == src_height), and wrk->x_add == 1.
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// => We special-case fxy_scale = 0, in WebPRescalerExportRow().
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wrk->fxy_scale = 0;
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} else {
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