{gif,img}2webp: sync -m help w/cwebp

These were both missing the mention of the default value (4).

Bug: webm:381109771
Change-Id: Ibb0d822310af443c5ff5219fc0334008de0a0c60

doc/tools.md

@@ -324,7 +324,7 @@ Per-frame options (only used for subsequent images input):
 -lossless ............ use lossless mode (default)
 -lossy ............... use lossy mode
 -q <float> ........... quality
--m <int> ............. method to use
+-m <int> ............. compression method (0=fast, 6=slowest), default=4
 -exact, -noexact ..... preserve or alter RGB values in transparent area
                        (default: -noexact, may cause artifacts
                                  with lossy animations)
@@ -359,7 +359,7 @@ Options:
 -sharp_yuv ............. use sharper (and slower) RGB->YUV conversion
                          (lossy only)
 -q <float> ............. quality factor (0:small..100:big)
--m <int> ............... compression method (0=fast, 6=slowest)
+-m <int> ............... compression method (0=fast, 6=slowest), default=4
 -min_size .............. minimize output size (default:off)
                          lossless compression by default; can be
                          combined with -q, -m, -lossy or -mixed

examples/gif2webp.c

@@ -77,7 +77,8 @@ static void Help(void) {
                                     "conversion\n"
          "                           (lossy only)\n");
   printf("  -q <float> ............. quality factor (0:small..100:big)\n");
-  printf("  -m <int> ............... compression method (0=fast, 6=slowest)\n");
+  printf("  -m <int> ............... compression method (0=fast, 6=slowest), "
+         "default=4\n");
   printf("  -min_size .............. minimize output size (default:off)\n"
          "                           lossless compression by default; can be\n"
          "                           combined with -q, -m, -lossy or -mixed\n"

examples/img2webp.c

@@ -62,7 +62,8 @@ static void Help(void) {
   printf(" -lossless ............ use lossless mode (default)\n");
   printf(" -lossy ............... use lossy mode\n");
   printf(" -q <float> ........... quality\n");
-  printf(" -m <int> ............. method to use\n");
+  printf(" -m <int> ............. compression method (0=fast, 6=slowest), "
+         "default=4\n");
   printf(" -exact, -noexact ..... preserve or alter RGB values in transparent "
                                   "area\n"
          "                        (default: -noexact, may cause artifacts\n"

man/img2webp.1

@@ -1,5 +1,5 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH IMG2WEBP 1 "September 17, 2024"
+.TH IMG2WEBP 1 "November 26, 2024"
 .SH NAME
 img2webp \- create animated WebP file from a sequence of input images.
 .SH SYNOPSIS
@@ -88,6 +88,10 @@ Specify the compression factor between 0 and 100. The default is 75.
 Specify the compression method to use. This parameter controls the
 trade off between encoding speed and the compressed file size and quality.
 Possible values range from 0 to 6. Default value is 4.
+When higher values are used, the encoder will spend more time inspecting
+additional encoding possibilities and decide on the quality gain.
+Lower value can result in faster processing time at the expense of
+larger file size and lower compression quality.
 .TP
 .B \-exact, \-noexact
 Preserve or alter RGB values in transparent area. The default is