From ee0f4e11ea1d81bbb08c1763c35d858bc105daf1 Mon Sep 17 00:00:00 2001
From: biggsbiggsby <33279473+biggsbiggsby@users.noreply.github.com>
Date: Fri, 17 Nov 2017 12:35:36 +0100
Subject: [PATCH] Update animation.jl

Changed palette for each frame to an option, made the default palette a lossless bmp file for best quality/filesize, but still compatible with FFMPEG 3.4 on Win7 x64
---
 src/animation.jl | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/src/animation.jl b/src/animation.jl
index 760a56d2..93f28427 100644
--- a/src/animation.jl
+++ b/src/animation.jl
@@ -67,13 +67,21 @@ mp4(anim::Animation, fn = mp4fn(); kw...) = buildanimation(anim.dir, fn, false;
 
 function buildanimation(animdir::AbstractString, fn::AbstractString,
                         is_animated_gif::Bool=true;
-                        fps::Integer = 20, loop::Integer = 0)
+                        fps::Integer = 20, loop::Integer = 0,
+                        variable_palette::Bool=false)
     fn = abspath(fn)
 
     if is_animated_gif
-        # generate a colorpalette for each frame to improve quality
-        palette="palettegen=stats_mode=single[pal],[0:v][pal]paletteuse=new=1"
-        run(`ffmpeg -v 0 -framerate $fps -loop $loop -i $(animdir)/%06d.png -lavfi "$palette" -y $fn`)
+        if variable_palette
+            # generate a colorpalette for each frame for highest quality, but larger filesize
+            palette="palettegen=stats_mode=single[pal],[0:v][pal]paletteuse=new=1"
+            run(`ffmpeg -v 0 -framerate $fps -loop $loop -i $(animdir)/%06d.png -lavfi "$palette" -y $fn`)
+        else
+            # generate a colorpalette first so ffmpeg does not have to guess it
+            run(`ffmpeg -v 0 -i $(animdir)/%06d.png -vf "palettegen=stats_mode=diff" -y "$(animdir)/palette.bmp"`)
+            # then apply the palette to get better results
+            run(`ffmpeg -v 0 -framerate $fps -loop $loop -i $(animdir)/%06d.png -i "$(animdir)/palette.bmp" -lavfi "paletteuse=dither=sierra2_4a" -y $fn`)
+        end
     else
         run(`ffmpeg -v 0 -framerate $fps -loop $loop -i $(animdir)/%06d.png -pix_fmt yuv420p -y $fn`)
     end