[MEncoder-users] Patch: add big-endian pcm encoder

Grant Edwards grante at visi.com
Tue Jan 9 23:38:56 CET 2007


I needed to be able to encode to 16-bit uncompressed big-endian
PCM.  I couldn't get either "-format sb16be" or "-af format=s16be" 
to encode to big-endian format, so I gave up and added a "pcms"
audio encoder that swaps the byte-order of the data stream.  In
order to get lavf containers to label the stream correctly, I
had to invent a new "wav" audio tag for big-endian PCM.

Although it works I have a feeling that this wasn't really the
"right" way to do it.  If anybody would care to comment or
suggest a better way to get big-endian PCM output please feel
free to do so.

Anyway, the patch is available at 

http://www.visi.com/~grante/sansa/mplayer-1.0rc1-encode-bigendian-pcm.patch

and is also included below.

--------------------------------8<--------------------------------------
diff -r -U9 MPlayer-1.0rc1/cfg-mencoder.h MPlayer-1.0rc1gbe/cfg-mencoder.h
--- MPlayer-1.0rc1/cfg-mencoder.h	2006-10-22 17:32:31.000000000 -0500
+++ MPlayer-1.0rc1gbe/cfg-mencoder.h	2007-01-08 11:20:59.000000000 -0600
@@ -86,18 +86,19 @@
 	"   x264     - H.264 encoding\n"
 #endif
 	"\n", CONF_TYPE_PRINT, CONF_NOCFG, 0, 0, NULL},
 	{NULL, NULL, 0, 0, 0, 0, NULL}
 };
 
 m_option_t oac_conf[]={
 	{"copy", &out_audio_codec, CONF_TYPE_FLAG, 0, 0, ACODEC_COPY, NULL},
 	{"pcm", &out_audio_codec, CONF_TYPE_FLAG, 0, 0, ACODEC_PCM, NULL},
+	{"pcms", &out_audio_codec, CONF_TYPE_FLAG, 0, 0, ACODEC_PCMS, NULL},
 #ifdef HAVE_MP3LAME
 	{"mp3lame", &out_audio_codec, CONF_TYPE_FLAG, 0, 0, ACODEC_VBRMP3, NULL},
 #else
 	{"mp3lame", "MPlayer was compiled without libmp3lame support.\n", CONF_TYPE_PRINT, CONF_NOCFG, 0, 0, NULL},
 #endif
 #ifdef USE_LIBAVCODEC
 	{"lavc", &out_audio_codec, CONF_TYPE_FLAG, 0, 0, ACODEC_LAVC, NULL},
 #else
 	{"lavc", "MPlayer was compiled without libavcodec. See README or DOCS.\n", CONF_TYPE_PRINT, CONF_NOCFG, 0, 0, NULL},
@@ -114,18 +115,19 @@
 #endif
 #ifdef HAVE_FAAC
 	{"faac", &out_audio_codec, CONF_TYPE_FLAG, 0, 0, ACODEC_FAAC, NULL},
 #else
 	{"faac", "MPlayer was compiled without libfaac. See README or DOCS.\n", CONF_TYPE_PRINT, CONF_NOCFG, 0, 0, NULL},
 #endif
 	{"help", "\nAvailable codecs:\n"
 	"   copy     - frame copy, without re-encoding (useful for AC3)\n"
 	"   pcm      - uncompressed PCM audio\n"
+	"   pcms     - uncompressed PCM audio (byteswapped)\n"
 #ifdef HAVE_MP3LAME
 	"   mp3lame  - cbr/abr/vbr MP3 using libmp3lame\n"
 #endif
 #ifdef USE_LIBAVCODEC
 	"   lavc     - FFmpeg audio encoder (MP2, AC3, ...)\n"
 #endif
 #ifdef HAVE_TOOLAME
 	"   toolame  - Toolame MP2 audio encoder\n"
 #endif
Only in MPlayer-1.0rc1gbe: cfg-mencoder.h-orig
diff -r -U9 MPlayer-1.0rc1/libavformat/riff.c MPlayer-1.0rc1gbe/libavformat/riff.c
--- MPlayer-1.0rc1/libavformat/riff.c	2006-10-22 17:32:34.000000000 -0500
+++ MPlayer-1.0rc1gbe/libavformat/riff.c	2007-01-09 13:41:45.000000000 -0600
@@ -166,18 +166,19 @@
     { CODEC_ID_NONE, 0 },
 };
 
 const CodecTag codec_wav_tags[] = {
     { CODEC_ID_MP2, 0x50 },
     { CODEC_ID_MP3, 0x55 },
     { CODEC_ID_AC3, 0x2000 },
     { CODEC_ID_DTS, 0x2001 },
     { CODEC_ID_PCM_S16LE, 0x01 },
+    { CODEC_ID_PCM_S16BE, 0x9999 },
     { CODEC_ID_PCM_U8, 0x01 }, /* must come after s16le in this list */
     { CODEC_ID_PCM_S24LE, 0x01 },
     { CODEC_ID_PCM_S32LE, 0x01 },
     { CODEC_ID_PCM_ALAW, 0x06 },
     { CODEC_ID_PCM_MULAW, 0x07 },
     { CODEC_ID_ADPCM_MS, 0x02 },
     { CODEC_ID_ADPCM_IMA_WAV, 0x11 },
     { CODEC_ID_ADPCM_YAMAHA, 0x20 },
     { CODEC_ID_ADPCM_G726, 0x45 },
diff -r -U9 MPlayer-1.0rc1/libmpcodecs/ae.c MPlayer-1.0rc1gbe/libmpcodecs/ae.c
--- MPlayer-1.0rc1/libmpcodecs/ae.c	2006-10-22 17:32:24.000000000 -0500
+++ MPlayer-1.0rc1gbe/libmpcodecs/ae.c	2007-01-08 11:23:15.000000000 -0600
@@ -43,18 +43,22 @@
 	encoder = (audio_encoder_t *) calloc(1, sizeof(audio_encoder_t));
 	memcpy(&encoder->params, params, sizeof(audio_encoding_params_t));
 	encoder->stream = stream;
 	
 	switch(stream->codec)
 	{
 		case ACODEC_PCM:
 			ris = mpae_init_pcm(encoder);
 			break;
+          
+		case ACODEC_PCMS:
+			ris = mpae_init_pcms(encoder);
+			break;
 #ifdef HAVE_TOOLAME
 		case ACODEC_TOOLAME:
 			ris = mpae_init_toolame(encoder);
 			break;
 #endif
 #ifdef USE_LIBAVCODEC
 		case ACODEC_LAVC:
 			ris = mpae_init_lavc(encoder);
 			break;
diff -r -U9 MPlayer-1.0rc1/libmpcodecs/ae.h MPlayer-1.0rc1gbe/libmpcodecs/ae.h
--- MPlayer-1.0rc1/libmpcodecs/ae.h	2006-10-22 17:32:24.000000000 -0500
+++ MPlayer-1.0rc1gbe/libmpcodecs/ae.h	2007-01-08 11:26:21.000000000 -0600
@@ -4,18 +4,19 @@
 
 #define ACODEC_COPY 0
 #define ACODEC_PCM 1
 #define ACODEC_VBRMP3 2
 #define ACODEC_NULL 3
 #define ACODEC_LAVC 4
 #define ACODEC_TOOLAME 5
 #define ACODEC_FAAC 6
 #define ACODEC_TWOLAME 7
+#define ACODEC_PCMS 99
 
 #define AE_NEEDS_COMPRESSED_INPUT 1
 
 typedef struct {
 	int channels;
 	int sample_rate;
 	int bitrate;
 	int samples_per_frame;
 	int audio_preload;
diff -r -U9 MPlayer-1.0rc1/libmpcodecs/ae_pcm.c MPlayer-1.0rc1gbe/libmpcodecs/ae_pcm.c
--- MPlayer-1.0rc1/libmpcodecs/ae_pcm.c	2006-10-22 17:32:24.000000000 -0500
+++ MPlayer-1.0rc1gbe/libmpcodecs/ae_pcm.c	2007-01-08 13:18:37.000000000 -0600
@@ -65,9 +65,63 @@
 	encoder->bind = bind_pcm;
 	encoder->get_frame_size = get_frame_size;
 	encoder->set_decoded_len = set_decoded_len;
 	encoder->encode = encode_pcm;
 	encoder->close = close_pcm;
 	
 	return 1;
 }
 
+
+
+//==================================================
+//Byteswapped version
+static int bind_pcms(audio_encoder_t *encoder, muxer_stream_t *mux_a)
+{
+  mux_a->h.dwScale=1;
+  mux_a->h.dwRate=encoder->params.sample_rate;
+  mux_a->wf=malloc(sizeof(WAVEFORMATEX));
+  mux_a->wf->wFormatTag= 0x9999;
+  mux_a->wf->nChannels=encoder->params.channels;
+  mux_a->h.dwSampleSize=2*mux_a->wf->nChannels;
+  mux_a->wf->nBlockAlign=mux_a->h.dwSampleSize;
+  mux_a->wf->nSamplesPerSec=mux_a->h.dwRate;
+  mux_a->wf->nAvgBytesPerSec=mux_a->h.dwSampleSize*mux_a->wf->nSamplesPerSec;
+  mux_a->wf->wBitsPerSample=16;
+  mux_a->wf->cbSize=0; // FIXME for l3codeca.acm
+	
+  encoder->input_format = (mux_a->wf->wBitsPerSample==8) ? AF_FORMAT_U8 : AF_FORMAT_S16_LE;
+  encoder->min_buffer_size = 16384;
+  encoder->max_buffer_size = mux_a->wf->nAvgBytesPerSec;
+	
+  return 1;
+}
+
+
+static int encode_pcms(audio_encoder_t *encoder, uint8_t *dest, void *src, int nsamples, int max_size)
+{
+  int i;
+  max_size = min(nsamples, max_size);
+  memcpy(dest, src, max_size);
+  for (i=0; i<(max_size-1); i+=2)
+    {
+      uint8_t t = dest[i];
+      dest[i] = dest[i+1];
+      dest[i+1] = t;
+    }
+  return max_size;
+}
+
+int mpae_init_pcms(audio_encoder_t *encoder)
+{
+  encoder->params.samples_per_frame = encoder->params.sample_rate;
+  encoder->params.bitrate = encoder->params.sample_rate * encoder->params.channels * 2 * 8;
+  
+  encoder->decode_buffer_size = encoder->params.bitrate / 8;
+  encoder->bind = bind_pcms;
+  encoder->get_frame_size = get_frame_size;
+  encoder->set_decoded_len = set_decoded_len;
+  encoder->encode = encode_pcms;
+  encoder->close = close_pcm;
+  
+  return 1;
+}
Only in MPlayer-1.0rc1gbe/libmpcodecs: ae_pcm.c-orig
diff -r -U9 MPlayer-1.0rc1/libmpcodecs/ae_pcm.h MPlayer-1.0rc1gbe/libmpcodecs/ae_pcm.h
--- MPlayer-1.0rc1/libmpcodecs/ae_pcm.h	2006-10-22 17:32:24.000000000 -0500
+++ MPlayer-1.0rc1gbe/libmpcodecs/ae_pcm.h	2007-01-08 11:53:00.000000000 -0600
@@ -1,8 +1,9 @@
 #ifndef __AE_PCM_H_
 #define __AE_PCM_H_
 
 #include "ae.h"
 
 int mpae_init_pcm(audio_encoder_t *encoder);
+int mpae_init_pcms(audio_encoder_t *encoder);
 
 #endif
diff -r -U9 MPlayer-1.0rc1/mencoder.c MPlayer-1.0rc1gbe/mencoder.c
--- MPlayer-1.0rc1/mencoder.c	2006-10-22 17:32:31.000000000 -0500
+++ MPlayer-1.0rc1gbe/mencoder.c	2007-01-08 11:22:35.000000000 -0600
@@ -12,18 +12,19 @@
 
 #define ACODEC_COPY 0
 #define ACODEC_PCM 1
 #define ACODEC_VBRMP3 2
 #define ACODEC_NULL 3
 #define ACODEC_LAVC 4
 #define ACODEC_TOOLAME 5
 #define ACODEC_FAAC 6
 #define ACODEC_TWOLAME 7
+#define ACODEC_PCMS 99
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <signal.h>
 #include "config.h"
 
 #ifdef __MINGW32__
 #define        SIGHUP 1
--------------------------------8<--------------------------------------

-- 
Grant Edwards                   grante             Yow!  Yow! Those people
                                  at               look exactly like Donnie
                               visi.com            and Marie Osmond!!




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