Extended oss output driver and libac3 to support 4 and 6 channel output mixes. added -channels command line option

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@3182 b3059339-0415-0410-9bf9-f77b7e298cf2

4 files changed, 43 insertions, 18 deletions

diff --git a/cfg-mplayer.h b/cfg-mplayer.h
index 0ce55ab9e9..74dab8c60b 100644
--- a/cfg-mplayer.h
+++ b/cfg-mplayer.h
@@ -74,6 +74,9 @@ extern int pl_delay_len;
 /* from libvo/aspect.c */
 extern float monitor_aspect;
 
+/* from dec_audio, currently used for ac3surround decoder only */
+extern int audio_output_channels;
+
 /*
  * CONF_TYPE_FUNC_FULL :
  * allows own implemtations for passing the params
@@ -103,6 +106,7 @@ struct config conf[]={
 	{"dsp", "Use -ao oss:dsp_path!\n", CONF_TYPE_PRINT, CONF_NOCFG, 0, 0},
         {"mixer", &mixer_device, CONF_TYPE_STRING, 0, 0, 0},
         {"master", &mixer_usemaster, CONF_TYPE_FLAG, 0, 0, 1},
+	{"channels", &audio_output_channels, CONF_TYPE_INT, CONF_RANGE, 2, 6},
 #ifdef HAVE_X11
 	{"display", &mDisplayName, CONF_TYPE_STRING, 0, 0, 0},
 #endif
diff --git a/dec_audio.c b/dec_audio.c
index c13c2880ab..52de2bebf2 100644
--- a/dec_audio.c
+++ b/dec_audio.c
@@ -83,6 +83,9 @@ static struct mad_stream mad_stream;
 static struct mad_frame  mad_frame;
 static struct mad_synth  mad_synth;
 
+/* used for ac3surround decoder - set using -channels option */
+int audio_output_channels = 2;
+
 
 // ensure buffer is filled with some data
 static void mad_prepare_buffer(sh_audio_t* sh_audio, struct mad_stream* ms, int length)
@@ -228,7 +231,8 @@ case AFM_ALAW:
   break;
 case AFM_AC3:
   // Dolby AC3 audio:
-  sh_audio->audio_out_minsize=4*256*6;
+  // however many channels, 2 bytes in a word, 256 samples in a block, 6 blocks in a frame
+  sh_audio->audio_out_minsize=audio_output_channels*2*256*6;
   break;
 case AFM_HWAC3:
   // Dolby AC3 audio:
@@ -329,7 +333,7 @@ case AFM_AC3: {
   // Dolby AC3 audio:
   dec_audio_sh=sh_audio; // save sh_audio for the callback:
   ac3_config.fill_buffer_callback = ac3_fill_buffer;
-  ac3_config.num_output_ch = 2;
+  ac3_config.num_output_ch = audio_output_channels;
   ac3_config.flags = 0;
 if(gCpuCaps.hasMMX){
   ac3_config.flags |= AC3_MMX_ENABLE;
@@ -342,7 +346,7 @@ if(gCpuCaps.has3DNow){
   if(sh_audio->ac3_frame){
     ac3_frame_t* fr=(ac3_frame_t*)sh_audio->ac3_frame;
     sh_audio->samplerate=fr->sampling_rate;
-    sh_audio->channels=2;
+    sh_audio->channels=ac3_config.num_output_ch;
     // 1 frame: 6*256 samples     1 sec: sh_audio->samplerate samples
     //sh_audio->i_bps=fr->frame_size*fr->sampling_rate/(6*256);
     sh_audio->i_bps=fr->bit_rate*(1000/8);
diff --git a/help_mp-en.h b/help_mp-en.h
index 776179e01a..577123a85a 100644
--- a/help_mp-en.h
+++ b/help_mp-en.h
@@ -33,6 +33,7 @@ static char help_text[]=
 #ifdef USE_FAKE_MONO
 " -stereo <mode>  select MPEG1 stereo output (0:stereo 1:left 2:right)\n"
 #endif
+" -channels <n>   target number of audio output channels\n"
 " -fs -vm -zoom   fullscreen playing options (fullscr,vidmode chg,softw.scale)\n"
 " -x <x> -y <y>   scale image to <x> * <y> resolution [if -vo driver supports!]\n"
 " -sub <file>     specify subtitle file to use (see also -subfps, -subdelay)\n"
diff --git a/libao2/ao_oss.c b/libao2/ao_oss.c
index 82da0df89e..aad1c943d6 100644
--- a/libao2/ao_oss.c
+++ b/libao2/ao_oss.c
@@ -26,6 +26,8 @@ static ao_info_t info =
 	""
 };
 
+/* Support for >2 output channels added 2001-11-25 - Steve Davies <steve@daviesfam.org> */
+
 LIBAO_EXTERN(oss)
 
 static char *dsp="/dev/dsp";
@@ -95,8 +97,8 @@ static int control(int cmd,int arg){
 // return: 1=success 0=fail
 static int init(int rate,int channels,int format,int flags){
 
-//  printf("ao2: %d Hz  %d chans  %s\n",rate,channels,
-//    audio_out_format_name(format));
+  printf("ao2: %d Hz  %d chans  %s\n",rate,channels,
+    audio_out_format_name(format));
 
   if (ao_subdevice)
     dsp = ao_subdevice;
@@ -124,13 +126,26 @@ static int init(int rate,int channels,int format,int flags){
     audio_out_format_name(ao_data.format), audio_out_format_name(format));
   
   if(format != AFMT_AC3) {
-  ao_data.channels=channels-1;
-  ioctl (audio_fd, SNDCTL_DSP_STEREO, &ao_data.channels);
-  
-  // set rate
-  ao_data.samplerate=rate;
-  ioctl (audio_fd, SNDCTL_DSP_SPEED, &ao_data.samplerate);
-  printf("audio_setup: using %d Hz samplerate (requested: %d)\n",ao_data.samplerate,rate);
+    // We only use SNDCTL_DSP_CHANNELS for >2 channels, in case some drivers don't have it
+    ao_data.channels = channels;
+    if (ao_data.channels > 2) {
+      if (ioctl (audio_fd, SNDCTL_DSP_CHANNELS, &ao_data.channels) == -1) {
+	printf("audio_setup: Failed to set audio device to %d channels\n", ao_data.channels);
+	return 0;
+      }
+    }
+    else {
+      int c = ao_data.channels-1;
+      if (ioctl (audio_fd, SNDCTL_DSP_STEREO, &c) == -1) {
+	printf("audio_setup: Failed to set audio device to %d channels\n", ao_data.channels);
+	return 0;
+      }
+    }
+    printf("audio_setup: using %d channels (requested: %d)\n", ao_data.channels, ao_data.channels);
+    // set rate
+    ao_data.samplerate=rate;
+    ioctl (audio_fd, SNDCTL_DSP_SPEED, &ao_data.samplerate);
+    printf("audio_setup: using %d Hz samplerate (requested: %d)\n",ao_data.samplerate,rate);
   }
 
   if(ioctl(audio_fd, SNDCTL_DSP_GETOSPACE, &zz)==-1){
@@ -195,8 +210,13 @@ static void reset(){
 
   ioctl (audio_fd, SNDCTL_DSP_SETFMT, &ao_data.format);
   if(ao_data.format != AFMT_AC3) {
-  ioctl (audio_fd, SNDCTL_DSP_STEREO, &ao_data.channels);
-  ioctl (audio_fd, SNDCTL_DSP_SPEED, &ao_data.samplerate);
+    if (ao_data.channels > 2)
+      ioctl (audio_fd, SNDCTL_DSP_CHANNELS, &ao_data.channels);
+    else {
+      int c = ao_data.channels-1;
+      ioctl (audio_fd, SNDCTL_DSP_STEREO, &c);
+    }
+    ioctl (audio_fd, SNDCTL_DSP_SPEED, &ao_data.samplerate);
   }
 }
 
@@ -267,7 +287,3 @@ static float get_delay(){
   }
   return ((float)ao_data.buffersize)/(float)ao_data.bps;
 }
-
-
-
-