Add ac3 encoding

Uses ffmpeg's ac3 encoder.


git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@3570 b64f7644-9d1e-0410-96f1-a4d463321fa5

1 files changed, 257 insertions, 0 deletions

diff --git a/libhb/encac3.c b/libhb/encac3.c
new file mode 100644
index 000000000..5c45b9800
--- /dev/null
+++ b/libhb/encac3.c
@@ -0,0 +1,257 @@
+/* $Id: encac3.c,v 1.23 2005/10/13 23:47:06 titer Exp $
+
+   This file is part of the HandBrake source code.
+   Homepage: <http://handbrake.fr/>.
+   It may be used under the terms of the GNU General Public License. */
+
+#include "hb.h"
+#include "hbffmpeg.h"
+#include "downmix.h"
+
+struct hb_work_private_s
+{
+    hb_job_t       * job;
+    AVCodecContext * context;
+
+    int              out_discrete_channels;
+    unsigned long    input_samples;
+    unsigned long    output_bytes;
+    hb_list_t      * list;
+    uint8_t        * buf;
+    int16_t        * samples;
+};
+
+int  encac3Init( hb_work_object_t *, hb_job_t * );
+int  encac3Work( hb_work_object_t *, hb_buffer_t **, hb_buffer_t ** );
+void encac3Close( hb_work_object_t * );
+
+#define AC3_SAMPLES_PER_FRAME 1536
+#define AC3_MAX_CODED_FRAME_SIZE 3840
+
+hb_work_object_t hb_encac3 =
+{
+    WORK_ENCAC3,
+    "AC-3 encoder (libavcodec)",
+    encac3Init,
+    encac3Work,
+    encac3Close
+};
+
+int encac3Init( hb_work_object_t * w, hb_job_t * job )
+{
+    AVCodec * codec;
+    AVCodecContext * context;
+    hb_audio_t * audio = w->audio;
+
+    hb_work_private_t * pv = calloc( 1, sizeof( hb_work_private_t ) );
+    w->private_data = pv;
+
+    pv->job = job;
+
+    pv->out_discrete_channels = HB_AMIXDOWN_GET_DISCRETE_CHANNEL_COUNT(audio->config.out.mixdown);
+    pv->input_samples = AC3_SAMPLES_PER_FRAME * pv->out_discrete_channels;
+    pv->output_bytes = AC3_MAX_CODED_FRAME_SIZE;
+
+    pv->buf = malloc( pv->input_samples * sizeof( float ) );
+    pv->samples = malloc( pv->input_samples * sizeof( int16_t ) );
+
+    codec = avcodec_find_encoder( CODEC_ID_AC3 );
+    if( !codec )
+    {
+        hb_log( "encac3Init: avcodec_find_encoder "
+                "failed" );
+    }
+    context = avcodec_alloc_context();
+
+    context->channel_layout = CH_LAYOUT_STEREO;
+    switch( audio->config.out.mixdown )
+    {
+        case HB_AMIXDOWN_MONO:
+            context->channel_layout = CH_LAYOUT_MONO;
+            break;
+
+        case HB_AMIXDOWN_STEREO:
+        case HB_AMIXDOWN_DOLBY:
+        case HB_AMIXDOWN_DOLBYPLII:
+            context->channel_layout = CH_LAYOUT_STEREO;
+            break;
+
+        case HB_AMIXDOWN_6CH:
+            context->channel_layout = CH_LAYOUT_5POINT0|CH_LOW_FREQUENCY;
+            break;
+
+        default:
+            hb_log(" encac3Init: bad mixdown" );
+            break;
+    }
+
+    context->bit_rate = audio->config.out.bitrate * 1000;
+    context->sample_rate = audio->config.out.samplerate;
+    context->channels = pv->out_discrete_channels;
+
+    if( hb_avcodec_open( context, codec ) )
+    {
+        hb_log( "encac3Init: avcodec_open failed" );
+    }
+    pv->context = context;
+
+    pv->list = hb_list_init();
+
+    return 0;
+}
+
+/***********************************************************************
+ * Close
+ ***********************************************************************
+ *
+ **********************************************************************/
+void encac3Close( hb_work_object_t * w )
+{
+    hb_work_private_t * pv = w->private_data;
+
+    if ( pv )
+    {
+        if( pv->context )
+        {
+            hb_deep_log( 2, "encac3: closing libavcodec" );
+            if ( pv->context->codec )
+                avcodec_flush_buffers( pv->context );
+            hb_avcodec_close( pv->context );
+        }
+
+        if ( pv->buf )
+        {
+            free( pv->buf );
+            pv->buf = NULL;
+        }
+
+        if ( pv->samples )
+        {
+            free( pv->samples );
+            pv->samples = NULL;
+        }
+
+        if ( pv->list )
+            hb_list_empty( &pv->list );
+
+        free( pv );
+        w->private_data = NULL;
+    }
+}
+
+static hb_buffer_t * Encode( hb_work_object_t * w )
+{
+    hb_work_private_t * pv = w->private_data;
+    uint64_t pts, pos;
+    hb_audio_t * audio = w->audio;
+    hb_buffer_t * buf;
+    int ii;
+
+    if( hb_list_bytes( pv->list ) < pv->input_samples * sizeof( float ) )
+    {
+        return NULL;
+    }
+
+    hb_list_getbytes( pv->list, pv->buf, pv->input_samples * sizeof( float ),
+                      &pts, &pos);
+
+    hb_chan_map_t *map = NULL;
+    if ( audio->config.in.codec == HB_ACODEC_AC3 )
+    {
+        map = &hb_ac3_chan_map;
+    }
+    else if ( audio->config.in.codec == HB_ACODEC_DCA )
+    {
+        map = &hb_qt_chan_map;
+    }
+    if ( map )
+    {
+        int layout;
+        switch (audio->config.out.mixdown)
+        {
+            case HB_AMIXDOWN_MONO:
+                layout = HB_INPUT_CH_LAYOUT_MONO;
+                break;
+            case HB_AMIXDOWN_STEREO:
+            case HB_AMIXDOWN_DOLBY:
+            case HB_AMIXDOWN_DOLBYPLII:
+                layout = HB_INPUT_CH_LAYOUT_STEREO;
+                break;
+            case HB_AMIXDOWN_6CH:
+            default:
+                layout = HB_INPUT_CH_LAYOUT_3F2R | HB_INPUT_CH_LAYOUT_HAS_LFE;
+                break;
+        }
+        hb_layout_remap( map, &hb_smpte_chan_map, layout, 
+                        (float*)pv->buf, AC3_SAMPLES_PER_FRAME);
+    }
+    
+    for (ii = 0; ii < pv->input_samples; ii++)
+    {
+        pv->samples[ii] = (int16_t)((float*)pv->buf)[ii];
+    }
+
+    buf = hb_buffer_init( pv->output_bytes );
+    buf->size = avcodec_encode_audio( pv->context, buf->data, buf->alloc,
+                                          pv->samples );
+
+    buf->start = pts + 90000 * pos / pv->out_discrete_channels / sizeof( float ) / audio->config.out.samplerate;
+    buf->stop  = buf->start + 90000 * AC3_SAMPLES_PER_FRAME / audio->config.out.samplerate;
+
+    buf->frametype = HB_FRAME_AUDIO;
+
+    if ( !buf->size )
+    {
+        hb_buffer_close( &buf );
+        return Encode( w );
+    }
+    else if (buf->size < 0)
+    {
+        hb_log( "encac3: avcodec_encode_audio failed" );
+        hb_buffer_close( &buf );
+        return NULL;
+    }
+
+    return buf;
+}
+
+/***********************************************************************
+ * Work
+ ***********************************************************************
+ *
+ **********************************************************************/
+int encac3Work( hb_work_object_t * w, hb_buffer_t ** buf_in,
+                    hb_buffer_t ** buf_out )
+{
+    hb_work_private_t * pv = w->private_data;
+    hb_buffer_t * in = *buf_in, * buf;
+
+    if ( in->size <= 0 )
+    {
+        /* EOF on input - send it downstream & say we're done */
+        *buf_out = in;
+        *buf_in = NULL;
+       return HB_WORK_DONE;
+    }
+
+    if ( pv->context == NULL || pv->context->codec == NULL )
+    {
+        // No encoder context. Nothing we can do.
+        return HB_WORK_OK;
+    }
+
+    hb_list_add( pv->list, in );
+    *buf_in = NULL;
+
+    *buf_out = buf = Encode( w );
+
+    while ( buf )
+    {
+        buf->next = Encode( w );
+        buf = buf->next;
+    }
+
+    return HB_WORK_OK;
+}
+
+