--- /dev/null
+/*****************************************************************************
+ * aes3.c: aes3 decoder/packetizer module
+ *****************************************************************************
+ * Copyright (C) 2008 the VideoLAN team
+ * $Id$
+ *
+ * Authors: Laurent Aimar <fenrir@videolan.org>
+ *
+ * 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 <assert.h>
+
+/*****************************************************************************
+ * Module descriptor
+ *****************************************************************************/
+static int OpenDecoder ( vlc_object_t * );
+static int OpenPacketizer( vlc_object_t * );
+static void Close ( vlc_object_t * );
+
+vlc_module_begin();
+
+ set_category( CAT_INPUT );
+ set_subcategory( SUBCAT_INPUT_ACODEC );
+ set_description( _("AES3/SMPTE 302M audio decoder") );
+ set_capability( "decoder", 100 );
+ set_callbacks( OpenDecoder, Close );
+
+ add_submodule();
+ set_description( N_("AES3/SMPTE 302M audio packetizer") );
+ set_capability( "packetizer", 100 );
+ set_callbacks( OpenPacketizer, Close );
+
+vlc_module_end();
+
+/*****************************************************************************
+ * decoder_sys_t : aes3 decoder descriptor
+ *****************************************************************************/
+struct decoder_sys_t
+{
+ /*
+ * Output properties
+ */
+ audio_date_t end_date;
+};
+
+#define AES3_HEADER_LEN 4
+
+/*****************************************************************************
+ * Local prototypes
+ *****************************************************************************/
+static int Open( decoder_t *p_dec, bool b_packetizer );
+
+static block_t *Parse( decoder_t *p_dec, int *pi_frame_length, int *pi_bits,
+ block_t **pp_block, bool b_packetizer );
+
+static inline uint8_t Reverse8( int n )
+{
+ n = ((n >> 1) & 0x55) | ((n << 1) & 0xaa);
+ n = ((n >> 2) & 0x33) | ((n << 2) & 0xcc);
+ n = ((n >> 4) & 0x0f) | ((n << 4) & 0xf0);
+ return n;
+}
+
+/*****************************************************************************
+ * OpenDecoder:
+ *****************************************************************************/
+static int OpenDecoder( vlc_object_t *p_this )
+{
+ decoder_t *p_dec = (decoder_t*)p_this;
+
+ return Open( p_dec, false );
+}
+
+/*****************************************************************************
+ * OpenPacketizer:
+ *****************************************************************************/
+static int OpenPacketizer( vlc_object_t *p_this )
+{
+ decoder_t *p_dec = (decoder_t*)p_this;
+
+ return Open( p_dec, true );
+}
+
+/*****************************************************************************
+ * Close : aes3 decoder destruction
+ *****************************************************************************/
+static void Close( vlc_object_t *p_this )
+{
+ decoder_t *p_dec = (decoder_t*)p_this;
+ free( p_dec->p_sys );
+}
+
+/*****************************************************************************
+ * Decode: decodes an aes3 frame.
+ ****************************************************************************
+ * Beware, this function must be fed with complete frames (PES packet).
+ *****************************************************************************/
+static aout_buffer_t *Decode( decoder_t *p_dec, block_t **pp_block )
+{
+ decoder_sys_t *p_sys = p_dec->p_sys;
+ block_t *p_block;
+ aout_buffer_t *p_aout_buffer;
+ int i_frame_length, i_bits;
+
+ p_block = Parse( p_dec, &i_frame_length, &i_bits, pp_block, false );
+ if( !p_block )
+ return NULL;
+
+ p_aout_buffer = p_dec->pf_aout_buffer_new( p_dec, i_frame_length );
+ if( p_aout_buffer == NULL )
+ goto exit;
+
+ p_aout_buffer->start_date = aout_DateGet( &p_sys->end_date );
+ p_aout_buffer->end_date = aout_DateIncrement( &p_sys->end_date, i_frame_length );
+
+ p_block->i_buffer -= AES3_HEADER_LEN;
+ p_block->p_buffer += AES3_HEADER_LEN;
+
+ if( i_bits == 24 )
+ {
+ uint8_t *p_out = p_aout_buffer->p_buffer;
+
+ while( p_block->i_buffer / 7 )
+ {
+ p_out[0] = Reverse8( p_block->p_buffer[0] );
+ p_out[1] = Reverse8( p_block->p_buffer[1] );
+ p_out[2] = Reverse8( p_block->p_buffer[2] );
+
+ p_out[3] = (Reverse8( p_block->p_buffer[3] ) >> 4) | ( (Reverse8( p_block->p_buffer[4] ) << 4) & 0xf0 );
+ p_out[4] = (Reverse8( p_block->p_buffer[4] ) >> 4) | ( (Reverse8( p_block->p_buffer[5] ) << 4) & 0xf0 );
+ p_out[5] = (Reverse8( p_block->p_buffer[5] ) >> 4) | ( (Reverse8( p_block->p_buffer[6] ) << 4) & 0xf0 );
+
+ p_block->i_buffer -= 7;
+ p_block->p_buffer += 7;
+ p_out += 6;
+ }
+
+ }
+ else if( i_bits == 20 )
+ {
+ uint8_t *p_out = p_aout_buffer->p_buffer;
+
+ while( p_block->i_buffer / 6 )
+ {
+ p_out[0] = ( (Reverse8( p_block->p_buffer[0] ) << 4) & 0xf0 );
+ p_out[1] = ( Reverse8( p_block->p_buffer[0]) >> 4 ) | ( (Reverse8( p_block->p_buffer[1]) << 4 ) & 0xf0 );
+ p_out[2] = ( Reverse8( p_block->p_buffer[1]) >> 4 ) | ( (Reverse8( p_block->p_buffer[2]) << 4 ) & 0xf0 );
+
+ p_out[3] = ( (Reverse8( p_block->p_buffer[3] ) << 4) & 0xf0 );
+ p_out[4] = ( Reverse8( p_block->p_buffer[3]) >> 4 ) | ( (Reverse8( p_block->p_buffer[4]) << 4 ) & 0xf0 );
+ p_out[5] = ( Reverse8( p_block->p_buffer[4]) >> 4 ) | ( (Reverse8( p_block->p_buffer[5]) << 4 ) & 0xf0 );
+
+ p_block->i_buffer -= 6;
+ p_block->p_buffer += 6;
+ p_out += 6;
+ }
+ }
+ else
+ {
+ uint8_t *p_out = p_aout_buffer->p_buffer;
+
+ assert( i_bits == 16 );
+
+ while( p_block->i_buffer / 5 )
+ {
+ p_out[0] = Reverse8( p_block->p_buffer[0] );
+ p_out[1] = Reverse8( p_block->p_buffer[1] );
+
+ p_out[2] = (Reverse8( p_block->p_buffer[2] ) >> 4) | ( (Reverse8( p_block->p_buffer[3] ) << 4) & 0xf0 );
+ p_out[3] = (Reverse8( p_block->p_buffer[3] ) >> 4) | ( (Reverse8( p_block->p_buffer[4] ) << 4) & 0xf0 );
+
+ p_block->i_buffer -= 5;
+ p_block->p_buffer += 5;
+ p_out += 4;
+ }
+ }
+
+exit:
+ block_Release( p_block );
+ return p_aout_buffer;
+}
+
+/*****************************************************************************
+ * Packetize: packetizes an aes3 frame.
+ ****************************************************************************
+ * Beware, this function must be fed with complete frames (PES packet).
+ *****************************************************************************/
+static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
+{
+ decoder_sys_t *p_sys = p_dec->p_sys;
+ block_t *p_block;
+ int i_frame_length, i_bits;
+
+ p_block = Parse( p_dec, &i_frame_length, &i_bits, pp_block, true );
+ if( !p_block )
+ return NULL;
+
+ p_block->i_pts = p_block->i_dts = aout_DateGet( &p_sys->end_date );
+ p_block->i_length = aout_DateIncrement( &p_sys->end_date, i_frame_length ) - p_block->i_pts;
+
+ /* Just pass on the incoming frame */
+ return p_block;
+}
+
+/*****************************************************************************
+ *
+ ****************************************************************************/
+static int Open( decoder_t *p_dec, bool b_packetizer )
+{
+ decoder_sys_t *p_sys;
+
+ if( p_dec->fmt_in.i_codec != VLC_FOURCC('a','e','s','3') )
+ return VLC_EGENERIC;
+
+ /* Allocate the memory needed to store the decoder's structure */
+ p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) );
+
+ if( !p_sys )
+ return VLC_EGENERIC;
+
+ /* Misc init */
+ aout_DateInit( &p_sys->end_date, 48000 );
+ aout_DateSet( &p_sys->end_date, 0 );
+
+ /* Set output properties */
+ p_dec->fmt_out.i_cat = AUDIO_ES;
+ p_dec->fmt_out.audio.i_rate = 48000;
+
+ /* Set callback */
+ if( b_packetizer )
+ {
+ p_dec->fmt_out.i_codec = VLC_FOURCC('a','e','s','3');
+
+ p_dec->pf_decode_audio = NULL;
+ p_dec->pf_packetize = Packetize;
+ }
+ else
+ {
+ p_dec->pf_decode_audio = Decode;
+ p_dec->pf_packetize = NULL;
+ }
+ return VLC_SUCCESS;
+}
+
+static const unsigned int pi_original_channels[4] = {
+ AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT,
+ AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
+ AOUT_CHAN_CENTER | AOUT_CHAN_LFE,
+ AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
+ AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT |
+ AOUT_CHAN_CENTER | AOUT_CHAN_LFE,
+ AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT |
+ AOUT_CHAN_REARLEFT | AOUT_CHAN_REARRIGHT |
+ AOUT_CHAN_MIDDLELEFT | AOUT_CHAN_MIDDLERIGHT |
+ AOUT_CHAN_CENTER | AOUT_CHAN_LFE,
+};
+
+static block_t *Parse( decoder_t *p_dec, int *pi_frame_length, int *pi_bits,
+ block_t **pp_block, bool b_packetizer )
+{
+ decoder_sys_t *p_sys = p_dec->p_sys;
+ block_t *p_block;
+ uint32_t h;
+ unsigned int i_size;
+ int i_channels;
+ int i_id;
+ int i_bits;
+
+ if( !pp_block || !*pp_block ) return NULL;
+
+ p_block = *pp_block;
+ *pp_block = NULL; /* So the packet doesn't get re-sent */
+
+ /* Date management */
+ if( p_block->i_pts > 0 &&
+ p_block->i_pts != aout_DateGet( &p_sys->end_date ) )
+ {
+ aout_DateSet( &p_sys->end_date, p_block->i_pts );
+ }
+
+ if( !aout_DateGet( &p_sys->end_date ) )
+ {
+ /* We've just started the stream, wait for the first PTS. */
+ block_Release( p_block );
+ return NULL;
+ }
+
+ if( p_block->i_buffer <= AES3_HEADER_LEN )
+ {
+ msg_Err(p_dec, "frame is too short");
+ block_Release( p_block );
+ return NULL;
+ }
+
+ /*
+ * AES3 header :
+ * size: 16
+ * number channels 2
+ * channel_id 8
+ * bits per samples 2
+ * alignments 4
+ */
+
+ h = GetDWBE( p_block->p_buffer );
+ i_size = (h >> 16) & 0xffff;
+ i_channels = 2 + 2*( (h >> 14) & 0x03 );
+ i_id = (h >> 6) & 0xff;
+ i_bits = 16 + 4*( (h >> 4)&0x03 );
+
+ if( AES3_HEADER_LEN + i_size != p_block->i_buffer || i_bits > 24 )
+ {
+ msg_Err(p_dec, "frame has invalid header");
+ block_Release( p_block );
+ return NULL;
+ }
+
+ /* Set output properties */
+ if( b_packetizer )
+ {
+ p_dec->fmt_out.audio.i_bitspersample = i_bits;
+ }
+ else
+ {
+ p_dec->fmt_out.i_codec = i_bits == 16 ? VLC_FOURCC('s','1','6','l') : VLC_FOURCC('s','2','4','l');
+ p_dec->fmt_out.audio.i_bitspersample = i_bits == 16 ? 16 : 24;
+ }
+
+ p_dec->fmt_out.audio.i_channels = i_channels;
+ p_dec->fmt_out.audio.i_original_channels = pi_original_channels[i_channels];
+ p_dec->fmt_out.audio.i_physical_channels = pi_original_channels[i_channels] & AOUT_CHAN_PHYSMASK;
+
+ *pi_frame_length = (p_block->i_buffer - AES3_HEADER_LEN) / ( (4+i_bits) * i_channels / 8 );
+ *pi_bits = i_bits;
+ return p_block;
+}
+
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