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--- gtspring2009:howto:format [2009/03/21 10:40]
gibson
+++ gtspring2009:howto:format [2010/02/02 07:55] (current)
@@ Line 1: / Line 1: @@
+====== How to format movies ======
+===== matlab =====
+You can make movies in Matlab using %%avifile%% and related Matlab commands.
+The basics of this are
+  aviobj = avifile(filename, 'fps', fps);
+  for n=1:N;
+    ...make a plot...
+    fr = getframe(gcf);
+    aviobj = addframe(aviobj, fr);
+  end
+  aviobj = aviobj(close)
+See %%makemovie.m%% in the channelflow distribution for a complete example.
+===== conversion and compression =====
+On Linux Matlab produces only uncompressed AVI files. These can be huge (gigabytes). You can compress
+the AVIs and convert to other formats using %%mencoder%% (a command-line utility that usually is installed
+as part of the %%Mplayer%% package.
+To compress and save as AVI, run
+    mencoder -nosound -ovc lavc -of avi -lavcopts vcodec=wmv2:vbitrate=1600 input.avi -o output.avi
+To compress and save as FLV (flash video), run
+    mencoder -nosound -of lavf -lavfopts format=flv -ovc lavc -lavcopts vcodec=flv:vmax_b_frames=0:vbitrate=1600 input.avi -o output.flv
+You will probably need to adjust the bitrate (here 1600) to get a good balance of file size and video quality.
+For convenience you can turn these commands into shell functions by placing the following in a bash start-up file
+(probably either %%~/.bashrc%% or %%~/.bash_aliases%%).
+   function avicompress() {
+     mencoder -nosound -ovc lavc -of avi -lavcopts vcodec=wmv2:vbitrate=$1 $2 -o $3
+   }
+   function flvcompress() {
+     mencoder -nosound -of lavf -lavfopts format=flv -ovc lavc -lavcopts vcodec=flv:vmax_b_frames=0:vbitrate=$1 $2 -o $3
+   }
+which can then be run as follows
+   avicompress 1600 input.avi output.avi
+   flvcompress 1600 input.avi output.flv
+===== obsolete conversion scripts =====
+I used to be able to convert to Quicktime and MP4 using these scripts, but mp4creator is now unsupported
+and it no longer compiles.
+  function mp4compress() {
+    mencoder $2 -ovc x264 -x264encopts bitrate=$1 -nosound -o tmp.avi
+    mplayer -nolirc -nojoystick tmp.avi -dumpvideo -dumpfile tmp.h264
+    rm -f $3
+    mp4creator -create=tmp.h264 -rate=10 $3
+    rm tmp.h264 tmp.avi
+    mp4creator -hint=1 $3
+    mp4creator -optimize $3
+    mp4creator -list $3
+  }
+  function movcompress() {
+    mencoder -nosound -ovc x264 $1 -o tmp.avi
+    mplayer tmp.avi -dumpvideo -dumpfile tmp.h264
+    mp4creator -create=tmp.h264 -rate=29.97 tmp.mp4
+    mp4creator -hint=1 tmp.mp4
+    mp4creator -optimize tmp.mp4
+    mencoder -nosound -ovc copy -of lavf -o $2 tmp.mp4 -lavfopts i_certify_that_my_video_stream_does_not_use_b_frames
+  }
+  function mp2compress() {
+    ffmpeg -i $2 -vcodec mpeg2video -b ${1}k  $3
+  }
+  function mp1compress() {
+    ffmpeg -i $2 -vcodec mpeg1video -b ${1}k  $3
+  }
 ====== Preferences  ======
-Please make all videos and images in standard sizes and colors. This makes it much easier to display them in [[http://chaosbook.org/tutorials/index.html|web tutorials]] etc.
+Please make all videos and images in standard sizes and colors. This makes it much easier to display them in [[http://chaosbook.org/tutorials/index.html|web tutorials]] etc. --Predrag
 ===== Videos =====
@@ Line 15: / Line 93: @@
     * framing: please **crop movies** so they have as little dead area along the edges as possible
-===== Figures =====
+====== Images ======
   * pre-publication quality  images
@@ Line 22: / Line 100: @@
+===== How to resize PNGs =====
+To convert a PNG figure to the pixel size you prefer, use the ImageMagick %%convert%% command. For example,
+<code>
+convert -resize 400x300 bigfig.png justright.png
+</code>
+converts the 560x420 pixel figure %%bigfig.png%% to a 400x300 pixel figure %%justright.png%%.
+{{:gtspring2009:howto:bigfig.png|bigfig.png}} {{:gtspring2009:howto:justright.png|justright.png}}

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