shine: Forward port of fixed integer MP3 encoder.

The fixed integer MP3 encoder shine originates from the RockBox project. It was then adapted for vlc in branch 0.8.6-neuros.

NEWS

@@ -24,6 +24,7 @@ Demuxers:
 
 Encoders:
  * Dirac encoding using libdirac (supported in Ogg and in TS)
+ * Shine mp3 fixed point encoder
 
 Access:
  * RTSP authentication with Darwin Streaming Server

configure.ac

@@ -2902,6 +2902,16 @@ then
   VLC_ADD_PLUGIN([wma_fixed])
 fi
 
+dnl
+dnl shine fixed point mp3 encoder
+dnl
+AC_ARG_ENABLE(shine,
+  [  --enable-shine          shine mp3 encoding module (default disabled)])
+if test "${enable_shine}" = "yes"
+then
+  VLC_ADD_PLUGIN([shine])
+fi
+
 dnl
 dnl  mad plugin
 dnl
@@ -5917,6 +5927,7 @@ AC_CONFIG_FILES([
   modules/codec/avcodec/Makefile
   modules/codec/cmml/Makefile
   modules/codec/dmo/Makefile
+  modules/codec/shine/Makefile
   modules/codec/subtitles/Makefile
   modules/codec/spudec/Makefile
   modules/codec/wmafixed/Makefile

modules/codec/Modules.am

-SUBDIRS = cmml dmo avcodec subtitles spudec wmafixed xvmc
+SUBDIRS = cmml dmo avcodec shine subtitles spudec wmafixed xvmc
 SOURCES_a52 = a52.c
 SOURCES_dts = dts.c
 SOURCES_flac = flac.c

modules/codec/shine/Modules.am

+SOURCES_shine = shine_mod.c

modules/codec/shine/shine_mod.c

+/*****************************************************************************
+ * shine_mod.c: MP3 encoder using Shine, a fixed point implementation
+ *****************************************************************************
+ * Copyright (C) 2008-2009 M2X
+ *
+ * Authors: Rafaël Carré <rcarre@m2x.nl>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+/*****************************************************************************
+ * Preamble
+ *****************************************************************************/
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <vlc_common.h>
+#include <vlc_plugin.h>
+#include <vlc_codec.h>
+#include <vlc_aout.h>
+#include <vlc_block.h>
+#include <vlc_block_helper.h>
+#include <vlc_bits.h>
+
+#include <assert.h>
+#include <inttypes.h>
+
+/* shine.c uses a lot of static variables, so we include the C file to keep
+ * the scope.
+ * Note that it makes this decoder non reentrant, this is why we set
+ * b_reentrant to VLC_FALSE in the module initialisation */
+#include "shine.c"
+
+struct encoder_sys_t
+{
+    block_fifo_t *p_fifo;
+
+    unsigned int i_buffer;
+    uint8_t *p_buffer;
+};
+
+/*****************************************************************************
+ * Local prototypes
+ *****************************************************************************/
+static int  OpenEncoder   ( vlc_object_t * );
+static void CloseEncoder  ( vlc_object_t * );
+
+static block_t *EncodeFrame  ( encoder_t *, aout_buffer_t * );
+
+vlc_module_begin();
+    set_category( CAT_INPUT );
+    set_subcategory( SUBCAT_INPUT_ACODEC );
+    set_description( _("MP3 fixed point audio encoder") );
+    set_capability( "encoder", 101 );
+    set_callbacks( OpenEncoder, CloseEncoder );
+vlc_module_end();
+
+static int OpenEncoder( vlc_object_t *p_this )
+{
+    encoder_t *p_enc = (encoder_t*)p_this;
+    encoder_sys_t *p_sys;
+
+    /* FIXME: what about layers 1 and 2 ? shine is an 'MP3' encoder */
+    if( p_enc->fmt_out.i_codec != VLC_FOURCC('m','p','3',' ') ||
+        p_enc->fmt_out.audio.i_channels > 2 )
+        return VLC_EGENERIC;
+
+    /* Shine is strict on its input */
+    if( p_enc->fmt_in.audio.i_channels != 2 )
+    {
+        msg_Err( p_enc, "Only stereo input is accepted, rejecting %d channels",
+            p_enc->fmt_in.audio.i_channels );
+        return VLC_EGENERIC;
+    }
+
+    p_sys = p_enc->p_sys = malloc( sizeof( encoder_sys_t ) );
+    if( !p_sys )
+        return VLC_ENOMEM;
+    memset( p_sys, 0, sizeof( encoder_sys_t ) );
+
+    if( !( p_sys->p_fifo = block_FifoNew() ) )
+    {
+        free( p_sys );
+        return VLC_ENOMEM;
+    }
+
+    init_mp3_encoder_engine( p_enc->fmt_out.audio.i_rate,
+        p_enc->fmt_out.audio.i_channels, p_enc->fmt_out.i_bitrate / 1000 );
+
+    p_enc->pf_encode_audio = EncodeFrame;
+
+    return VLC_SUCCESS;
+}
+
+/* We split/pack PCM blocks to a fixed size: pcm_chunk_size bytes */
+static block_t *GetPCM( encoder_t *p_enc, aout_buffer_t *p_block )
+{
+    encoder_sys_t *p_sys = p_enc->p_sys;
+    block_t *p_pcm_block;
+
+    if( !p_block ) goto buffered; /* just return a block if we can */
+
+    /* Put the PCM samples sent by VLC in the Fifo */
+    while( p_sys->i_buffer + p_block->i_nb_bytes >= pcm_chunk_size )
+    {
+        unsigned int i_buffer = 0;
+        p_pcm_block = block_New( p_enc, pcm_chunk_size );
+        if( !p_pcm_block ) break;
+
+        if( p_sys->i_buffer )
+        {
+            vlc_memcpy( p_pcm_block->p_buffer, p_sys->p_buffer,
+                p_sys->i_buffer );
+
+            i_buffer = p_sys->i_buffer;
+            p_sys->i_buffer = 0;
+            free( p_sys->p_buffer );
+        }
+
+        vlc_memcpy( p_pcm_block->p_buffer + i_buffer,
+            p_block->p_buffer , pcm_chunk_size - i_buffer );
+        p_block->p_buffer += pcm_chunk_size - i_buffer;
+
+        p_block->i_nb_bytes -= pcm_chunk_size - i_buffer;
+
+        block_FifoPut( p_sys->p_fifo, p_pcm_block );
+    }
+
+    /* We hadn't enough data to make a block, put it in standby */
+    if( p_block->i_nb_bytes )
+    {
+        p_sys->p_buffer = p_sys->i_buffer ?
+            realloc( p_sys->p_buffer, p_block->i_nb_bytes + p_sys->i_buffer ) :
+            malloc( p_block->i_nb_bytes );
+
+        if( !p_sys->p_buffer )
+        {
+            p_sys->i_buffer = 0;
+            return NULL;
+        }
+
+        vlc_memcpy( p_sys->p_buffer + p_sys->i_buffer,
+            p_block->p_buffer, p_block->i_nb_bytes );
+
+        p_sys->i_buffer += p_block->i_nb_bytes;
+        p_block->i_nb_bytes = 0;
+    }
+
+buffered:
+    /* and finally get a block back */
+    return block_FifoCount( p_sys->p_fifo ) > 0 ? block_FifoGet( p_sys->p_fifo ) : NULL;
+}
+
+static block_t *EncodeFrame( encoder_t *p_enc, aout_buffer_t *p_block )
+{
+    block_t *p_pcm_block;
+    block_t *p_chain = NULL;
+    unsigned int i_samples = p_block->i_nb_bytes / 4 /* s16l stereo */;
+    mtime_t start_date = p_block->start_date;
+    start_date -= i_samples * 1000000 / p_enc->fmt_out.audio.i_rate;
+
+    do {
+        if( !( p_pcm_block = GetPCM( p_enc, p_block ) ) )
+            break;
+
+        p_block = NULL; /* we don't need it anymore */
+
+        uint32_t enc_buffer[16384]; /* storage for 65536 Bytes XXX: too much */
+        struct enc_chunk_hdr *chunk = (void*) enc_buffer;
+        chunk->enc_data = ENC_CHUNK_SKIP_HDR(chunk->enc_data, chunk);
+
+        encode_frame( (char*)p_pcm_block->p_buffer, chunk );
+        block_Release( p_pcm_block );
+
+        block_t *p_mp3_block = block_New( p_enc, chunk->enc_size );
+        if( !p_mp3_block )
+            break;
+
+        vlc_memcpy( p_mp3_block->p_buffer, chunk->enc_data,
+            chunk->enc_size );
+
+        /* date management */
+        p_mp3_block->i_length = SAMP_PER_FRAME1 * 1000000 /
+            p_enc->fmt_out.audio.i_rate;
+
+        start_date += p_mp3_block->i_length;
+        p_mp3_block->i_dts = p_mp3_block->i_pts = start_date;
+
+        p_mp3_block->i_samples = SAMP_PER_FRAME1;
+
+        block_ChainAppend( &p_chain, p_mp3_block );
+    } while( p_pcm_block );
+
+    return p_chain;
+}
+
+static void CloseEncoder( vlc_object_t *p_this )
+{
+    encoder_sys_t *p_sys = ((encoder_t*)p_this)->p_sys;
+
+    /* TODO: we should send the last PCM block padded with 0
+     * But we don't know if other blocks will come before it's too late */
+    if( p_sys->i_buffer )
+        free( p_sys->p_buffer );
+
+    block_FifoRelease( p_sys->p_fifo );
+    free( p_sys );
+}