From 1e595fe1e8bf47f81f4d0051720738c5011b9d8e Mon Sep 17 00:00:00 2001
From: James Zern <jzern@google.com>
Date: Thu, 13 Aug 2015 20:54:02 -0700
Subject: [PATCH] dwebp: add -resize as a synonym for -scale

-resize is used in cwebp for the same purpose

Change-Id: I2756f3d23c4799fc9a10c4fe8c4c17057beebca9
---
 examples/dwebp.c | 5 +++--
 man/dwebp.1      | 8 +++++---
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/examples/dwebp.c b/examples/dwebp.c
index 5785b483..4d95819f 100644
--- a/examples/dwebp.c
+++ b/examples/dwebp.c
@@ -549,7 +549,7 @@ static void Help(void) {
          "  -alpha_dither  use alpha-plane dithering if needed\n"
          "  -mt .......... use multi-threading\n"
          "  -crop <x> <y> <w> <h> ... crop output with the given rectangle\n"
-         "  -scale <w> <h> .......... scale the output (*after* any cropping)\n"
+         "  -resize <w> <h> ......... scale the output (*after* any cropping)\n"
          "  -flip ........ flip the output vertically\n"
          "  -alpha ....... only save the alpha plane\n"
          "  -incremental . use incremental decoding (useful for tests)\n"
@@ -627,7 +627,8 @@ int main(int argc, const char *argv[]) {
       config.options.crop_top    = ExUtilGetInt(argv[++c], 0, &parse_error);
       config.options.crop_width  = ExUtilGetInt(argv[++c], 0, &parse_error);
       config.options.crop_height = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-scale") && c < argc - 2) {
+    } else if ((!strcmp(argv[c], "-scale") || !strcmp(argv[c], "-resize")) &&
+               c < argc - 2) {  // '-scale' is left for compatibility
       config.options.use_scaling = 1;
       config.options.scaled_width  = ExUtilGetInt(argv[++c], 0, &parse_error);
       config.options.scaled_height = ExUtilGetInt(argv[++c], 0, &parse_error);
diff --git a/man/dwebp.1 b/man/dwebp.1
index 5741be6a..0e7cd985 100644
--- a/man/dwebp.1
+++ b/man/dwebp.1
@@ -1,5 +1,5 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH DWEBP 1 "June 13, 2014"
+.TH DWEBP 1 "August 13, 2015"
 .SH NAME
 dwebp \- decompress a WebP file to an image file
 .SH SYNOPSIS
@@ -90,11 +90,13 @@ Note: the cropping is applied \fIbefore\fP any scaling.
 .B \-flip
 Flip decoded image vertically (can be useful for OpenGL textures for instance).
 .TP
-.BI \-scale " width height
+\fB\-resize\fR, \fB\-scale\fI width height\fR
 Rescale the decoded picture to dimension \fBwidth\fP x \fBheight\fP. This
 option is mostly intended to reducing the memory needed to decode large images,
-when only a small version is needed (thumbnail, preview, etc.).  Note: scaling
+when only a small version is needed (thumbnail, preview, etc.). Note: scaling
 is applied \fIafter\fP cropping.
+If either (but not both) of the \fBwidth\fP or \fBheight\fP parameters is 0,
+the value will be calculated preserving the aspect-ratio.
 .TP
 .B \-v
 Print extra information (decoding time in particular).