mplayer: Make alsa work (use larger buffer), and use it instead of OSS This

reduces CPU load during playback, and also makes the audio mixer react much
more quickly (note: if mplayer automatic resampling kicks in now, we should
add -af-adv force=2 to make it use the fastest resampling filter)

mplayer/Makefile

@@ -10,7 +10,7 @@ PKG_NAME:=MPlayer
 PKG_REV:=33333
 FFMPEG_REV:=d84f191d37b8123203dff250531a4b4c0d5f587a
 PKG_VERSION:=r$(PKG_REV)
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 FFMPEG_SOURCE_URL:=git://git.videolan.org/ffmpeg.git
@@ -79,6 +79,8 @@ CONFIGURE_ARGS := --target=mips \
 		  --disable-vdpau					\
 		  --disable-gl						\
 		  --disable-xf86keysym					\
+		  --disable-ossaudio					\
+		  --enable-alsa						\
 		  --enable-vidix					\
 		  --disable-vidix-pcidb					\
 		  --with-vidix-drivers="no"				\

mplayer/README

@@ -1,11 +1,41 @@
-this is outdated; mpeg1 support currently disabled (patents?).
+1. prepare your video files for Ben:
 
-Use ffmpeg2theora  or ffmpeg with vp8, vorbis, mkv
+Use ffmpeg2theora or ffmpeg with vp8, vorbis, mkv.
 
-1. prepare your avi files for Ben:
+When using theora, try to use a video width and height that are a multiple of
+16.  Currently theora decoding displays strange borders, if size is not a
+multiple of 16.
 
-for i in $(echo "*.avi"); do /usr/bin/mencoder -o "$i.mpg" -vf scale=320:-2 -of mpeg -ovc lavc -lavcopts vcodec=mpeg1video:vpass=1:vbitrate=200 -ofps 24000/1001 -oac lavc -lavcopts acodec=mp2:abitrate=64 "$i" && /usr/bin/mencoder -o "$i.mpg" -vf scale=320:-2 -of mpeg -ovc lavc -lavcopts vcodec=mpeg1video:vpass=2:vbitrate=200 -ofps 24000/1001 -oac lavc -lavcopts acodec=mp2:abitrate=64 "$i"; done
+Try to use an audio sampling rate of 44100 for the vorbis audio.  If the
+automatic resampling of the alsa OSS emulation is triggered, quality degrades
+a lot.  Alternatively use 'mplayer -af resample=44100:1:1' on playback.
+
+For encoding try to use libtheora 1.2 ("ptalarbvorm") which improves visual
+qality a lot compared to previous versions.  Always encode with
+constant-quality *not* giving a bitrate target.
+
+Here's an example encoding command:
+
+ffmpeg2theora  -o output.ogv input.avi \
+	       -v8 -x320 -y176 \
+	       -a0 --channels 2  --samplerate 44100 
+
+Yielding a pretty high visual quality (-v8 i.e. "80%").  Use -v6 for
+approximately half the bitrate with moderate quality.
 
 2. play your files with Ben:
 
-mplayer -vo sdl -ac mad file.mpg
+mplayer output.ogv
+
+(Assumptions:
+
+the following options should be set in your ~/.mplayer/config:
+
+volume=10
+vo=cvidix
+screenw=320
+screenh=240
+fs=1
+ac=tremor
+quiet=1
+)

mplayer/patches/020-alsa-buffer.patch

@@ -0,0 +1,15 @@
+Index: MPlayer-r33304/libao2/ao_alsa.c
+===================================================================
+--- MPlayer-r33304.orig/libao2/ao_alsa.c	2011-04-27 08:12:35.000000000 +0200
++++ MPlayer-r33304/libao2/ao_alsa.c	2011-04-27 08:12:55.000000000 +0200
+@@ -313,8 +313,8 @@
+ */
+ static int init(int rate_hz, int channels, int format, int flags)
+ {
+-    unsigned int alsa_buffer_time = 500000; /* 0.5 s */
+-    unsigned int alsa_fragcount = 16;
++    unsigned int alsa_buffer_time = 1000000; /* 0.5 s */
++    unsigned int alsa_fragcount = 4;
+     int err;
+     int block;
+     strarg_t device;