--- /dev/null
+/*****************************************************************************
+ * mpeg_audio.c : mpeg_audio Stream input module for vlc
+ *****************************************************************************
+ * Copyright (C) 2001 VideoLAN
+ * $Id: mpeg_audio.c,v 1.1 2002/05/10 02:04:17 fenrir Exp $
+ * Authors: Laurent Aimar <fenrir@via.ecp.fr>
+ *
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ *****************************************************************************/
+
+/*****************************************************************************
+ * Preamble
+ *****************************************************************************/
+#include <stdlib.h> /* malloc(), free() */
+
+#include <videolan/vlc.h>
+
+#include <sys/types.h>
+
+#include "stream_control.h"
+#include "input_ext-intf.h"
+#include "input_ext-dec.h"
+#include "input_ext-plugins.h"
+
+/*****************************************************************************
+ * Local prototypes
+ *****************************************************************************/
+static void input_getfunctions( function_list_t * p_function_list );
+static int MPEGAudioDemux ( struct input_thread_s * );
+static int MPEGAudioInit ( struct input_thread_s * );
+static void MPEGAudioEnd ( struct input_thread_s * );
+
+/* TODO: support MPEG-2.5, not difficult */
+
+/*****************************************************************************
+ * Build configuration tree.
+ *****************************************************************************/
+MODULE_CONFIG_START
+MODULE_CONFIG_STOP
+
+MODULE_INIT_START
+ SET_DESCRIPTION( "MPEG I/II Audio stream demux" )
+ ADD_CAPABILITY( DEMUX, 110 )
+ ADD_SHORTCUT( "mpeg_audio" )
+MODULE_INIT_STOP
+
+MODULE_ACTIVATE_START
+ input_getfunctions( &p_module->p_functions->demux );
+MODULE_ACTIVATE_STOP
+
+MODULE_DEACTIVATE_START
+MODULE_DEACTIVATE_STOP
+
+/*****************************************************************************
+ * Functions exported as capabilities. They are declared as static so that
+ * we don't pollute the namespace too much.
+ *****************************************************************************/
+static void input_getfunctions( function_list_t * p_function_list )
+{
+#define input p_function_list->functions.demux
+ input.pf_init = MPEGAudioInit;
+ input.pf_end = MPEGAudioEnd;
+ input.pf_demux = MPEGAudioDemux;
+ input.pf_rewind = NULL;
+#undef input
+}
+
+/*****************************************************************************
+ * Definitions of structures and functions used by this plugins
+ *****************************************************************************/
+
+typedef struct mpegaudio_format_s
+{
+ u32 i_header;
+ int i_version;
+ int i_layer;
+ int i_crc;
+ int i_bitrate;
+ int i_samplingfreq;
+ int i_padding;
+ int i_extension;
+ int i_mode;
+ int i_modeext;
+ int i_copyright;
+ int i_original;
+ int i_emphasis;
+
+} mpegaudio_format_t;
+
+/* Xing Header if present */
+#define FRAMES_FLAG 0x0001 /* these flags is for i_flags */
+#define BYTES_FLAG 0x0002 /* because all is optionnal */
+#define TOC_FLAG 0x0004
+#define VBR_SCALE_FLAG 0x0008
+typedef struct mpegaudio_xing_header_s
+{
+ int i_flags; /* from Xing header data */
+ int i_frames; /* total bit stream frames from Xing header data */
+ int i_bytes; /* total bit stream bytes from Xing header data */
+ int i_vbr_scale; /* encoded vbr scale from Xing header data */
+ u8 i_toc[100]; /* for seek */
+ int i_avgbitrate; /* calculated, XXX: bits/sec not Kb */
+} mpegaudio_xing_header_t;
+
+typedef struct demux_data_mpegaudio_s
+{
+ mtime_t i_pts;
+
+ int i_framecount;
+
+ es_descriptor_t *p_es;
+ mpegaudio_format_t mpeg;
+ mpegaudio_xing_header_t xingheader;
+
+} demux_data_mpegaudio_t;
+
+
+static int mpegaudio_bitrate[2][3][16] =
+{
+ {
+ { 0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448, 0 }, /* v1 l1 */
+ { 0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384, 0 }, /* v1 l2 */
+ { 0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 0 } /* v1 l3 */
+ },
+
+ {
+ { 0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256, 0 }, /* v2 l1 */
+ { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 }, /* v2 l2 */
+ { 0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0 } /* v2 l3 */
+ }
+
+};
+
+static int mpegaudio_samplingfreq[2][4] = /* version 1 then 2 */
+{
+ { 44100, 48000, 32000, 0 },
+ { 22050, 24000, 16000, 0 }
+};
+
+static char* mpegaudio_mode[4] =
+{
+ "stereo", "joint stereo", "dual channel", "mono"
+};
+
+/*****************************************************************************
+ * MPEGAudio_CheckHeader : Test the validity of the header
+ *****************************************************************************/
+static int MPEGAudio_CheckHeader( u32 i_header )
+{
+ if( ((( i_header >> 20 )&0x0FFF) != 0x0FFF ) /* header sync */
+ || (((i_header >> 17)&0x03) == 0 ) /* valid layer ?*/
+ || (((i_header >> 12)&0x0F) == 0x0F )
+ || (((i_header >> 12)&0x0F) == 0x00 ) /* valid bitrate ? */
+ || (((i_header >> 10) & 0x03) == 0x03 ) /* valide sampling freq ? */
+ || ((i_header & 0x03) == 0x02 )) /* valid emphasis ? */
+ {
+ return( 0 ); /*invalid */
+ }
+ return( 1 ); /* valid */
+}
+
+/*****************************************************************************
+ * MPEGAudio_ParseHeader : Parse a header ;)
+ *****************************************************************************/
+static void MPEGAudio_ParseHeader( u32 i_header, mpegaudio_format_t *p_mpeg )
+{
+ p_mpeg->i_header = i_header;
+ p_mpeg->i_version = 1 - ( ( i_header >> 19 ) & 0x01 );
+ p_mpeg->i_layer = 3 - ( ( i_header >> 17 ) & 0x03 );
+ p_mpeg->i_crc = 1 - (( i_header >> 16 ) & 0x01);
+ p_mpeg->i_bitrate = mpegaudio_bitrate[p_mpeg->i_version][p_mpeg->i_layer][(i_header>>12)&0x0F];
+ p_mpeg->i_samplingfreq = mpegaudio_samplingfreq[p_mpeg->i_version][(i_header>>10)&0x03];
+ p_mpeg->i_padding = (( i_header >> 9 ) & 0x01);
+ p_mpeg->i_extension = ( i_header >> 7 ) & 0x01;
+ p_mpeg->i_mode = ( i_header >> 6 ) & 0x03;
+ p_mpeg->i_modeext = ( i_header >> 4 ) & 0x03;
+ p_mpeg->i_copyright = ( i_header >> 3 ) & 0x01;
+ p_mpeg->i_original = ( i_header >> 2 ) & 0x01;
+ p_mpeg->i_emphasis = ( i_header ) & 0x03;
+}
+
+/*****************************************************************************
+ * MPEGAudio_FrameSize : give the size of a frame in the mpeg stream
+ *****************************************************************************/
+static int MPEGAudio_FrameSize( mpegaudio_format_t *p_mpeg )
+{
+ /* XXX if crc do i need to add 2 bytes or not? */
+ switch( p_mpeg->i_layer )
+ {
+ case( 0 ):
+ return( ( ( ( !p_mpeg->i_version ? 12000 : 6000 ) *
+ p_mpeg->i_bitrate ) /
+ p_mpeg->i_samplingfreq + p_mpeg->i_padding ) * 4);
+ case( 1 ):
+ case( 2 ):
+ return( ( ( !p_mpeg->i_version ? 144000 : 72000 ) *
+ p_mpeg->i_bitrate ) /
+ p_mpeg->i_samplingfreq + p_mpeg->i_padding );
+ }
+ return( 1024 ); /* must never happen, 1k to advance in stream*/
+}
+
+/*****************************************************************************
+ * MPEGAudio_DecodedFrameSize : give the length of the decoded pcm data
+ *****************************************************************************/
+static int MPEGAudio_DecodedFrameSize( mpegaudio_format_t *p_mpeg )
+{
+ switch( p_mpeg->i_layer )
+ {
+ case( 0 ): /* layer 1 */
+ return( 384);
+ case( 1 ): /* layer 2 */
+ return( 1152 );
+ case( 2 ): /* layer 3 */
+ return( !p_mpeg->i_version ? 1152 : 576 );
+ /* XXX: perhaps we have to /2 for all layer but i'm not sure */
+ }
+ return( 0 );
+}
+
+/*****************************************************************************
+ * MPEGAudio_FindFrame : Find a header that could be valid.
+ *****************************************************************************
+ * The idea is to search for 2 consecutive headers that seem valid
+ * Perhaps we can search 2 header with same version or samplefreq(...) to be
+ * more secure but this seems to be enougth
+ *****************************************************************************/
+static int MPEGAudio_FindFrame( input_thread_t *p_input,
+ int *pi_pos,
+ mpegaudio_format_t *p_mpeg )
+{
+ byte_t *p_buff;
+ u32 i_header;
+ int i_framesize;
+
+ int i_pos = 0;
+ int i_size = input_Peek( p_input, &p_buff, 8192 );
+
+ while( i_pos + 4 <= i_size ) /* need at least 4 bytes */
+ {
+ i_header = U32_AT( p_buff );
+ if( MPEGAudio_CheckHeader( i_header ) )
+ {
+ MPEGAudio_ParseHeader( i_header, p_mpeg );
+ i_framesize = MPEGAudio_FrameSize( p_mpeg );
+ if( ( i_pos + i_framesize + 4 > i_size )
+ ||( MPEGAudio_CheckHeader( U32_AT( p_buff + i_framesize ) ) ) )
+ {
+ *pi_pos = i_pos;
+ return( 1 );
+ }
+ }
+ p_buff++;
+ i_pos++;
+ }
+
+ *pi_pos = 0;
+ return( 0 );
+}
+
+/*****************************************************************************
+ * MPEGAudio_ExtractXingHeader : extract a Xing header if exist
+ *****************************************************************************
+ * It also calcul avgbitrate, using Xing header if present or assume that
+ * the bitrate of the first frame is the same for the all file
+ *****************************************************************************/
+static void MPEGAudio_ExtractXingHeader( input_thread_t *p_input,
+ mpegaudio_xing_header_t *p_xh )
+{
+ int i_pos;
+ int i_size;
+ mpegaudio_format_t mpeg;
+ byte_t *p_buff;
+
+ p_xh->i_flags = 0; /* nothing present */
+ if( !(MPEGAudio_FindFrame( p_input, &i_pos, &mpeg )) )
+ {
+ return; /* failed , can't */
+ }
+ p_xh->i_avgbitrate = mpeg.i_bitrate * 1000; /* default */
+
+ /* 1024 is very very enougth */
+ if( ( i_size = input_Peek( p_input, &p_buff, 1024 + i_pos ) ) < 8 )
+ {
+ return;
+ }
+ p_buff += i_pos;
+
+ /* calculate pos of xing header */
+ if( !mpeg.i_version )
+ {
+ p_buff += mpeg.i_mode != 3 ? 36 : 21;
+ }
+ else
+ {
+ p_buff += mpeg.i_mode != 3 ? 21 : 13;
+ }
+
+ if( (*p_buff != 'X' )||(*(p_buff+1) != 'i' )
+ ||(*(p_buff+2) != 'n' )||(*(p_buff+3) != 'g' ) )
+ {
+ return;
+ }
+ p_buff += 4;
+
+ p_xh->i_flags = U32_AT( p_buff );
+ p_buff += 4;
+
+ if( p_xh->i_flags&FRAMES_FLAG )
+ {
+ p_xh->i_frames = U32_AT( p_buff );
+ p_buff += 4;
+ }
+ if( p_xh->i_flags&BYTES_FLAG )
+ {
+ p_xh->i_bytes = U32_AT( p_buff );
+ p_buff += 4;
+ }
+ if( p_xh->i_flags&TOC_FLAG )
+ {
+ FAST_MEMCPY( p_xh->i_toc, p_buff, 100 );
+ p_buff += 100;
+ }
+ if( p_xh->i_flags&VBR_SCALE_FLAG )
+ {
+ p_xh->i_vbr_scale = U32_AT( p_buff );
+ p_buff += 4;
+ }
+ if( ( p_xh->i_flags&FRAMES_FLAG )&&( p_xh->i_flags&BYTES_FLAG ) )
+ {
+ p_xh->i_avgbitrate =
+ ((u64)p_xh->i_bytes * (u64)8 * (u64)mpeg.i_samplingfreq) /
+ ((u64)p_xh->i_frames * (u64)MPEGAudio_DecodedFrameSize( &mpeg));
+ }
+}
+
+
+/*****************************************************************************
+ * MPEGaudioInit : initializes MPEGaudio structures
+ *****************************************************************************/
+static int MPEGAudioInit( input_thread_t * p_input )
+{
+ demux_data_mpegaudio_t *p_mpegaudio;
+ mpegaudio_format_t mpeg;
+ es_descriptor_t * p_es;
+ int i_pos;
+
+ /* XXX: i don't know what it's supposed to do, copied from ESInit */
+ /* Initialize access plug-in structures. */
+ if( p_input->i_mtu == 0 )
+ {
+ /* Improve speed. */
+ p_input->i_bufsize = INPUT_DEFAULT_BUFSIZE;
+ }
+
+ if( !(MPEGAudio_FindFrame( p_input, &i_pos, &mpeg )) )
+ {
+ intf_ErrMsg( "input: MPEGAudio plug-in discarded (no MPEG header)" );
+ return( -1 );
+ }
+
+ vlc_mutex_lock( &p_input->stream.stream_lock );
+ if( input_InitStream( p_input, 0 ) == -1)
+ {
+ intf_ErrMsg( "input error: cannot init stream" );
+ return( -1 );
+ }
+ if( input_AddProgram( p_input, 0, 0) == NULL )
+ {
+ intf_ErrMsg( "input error: cannot add program" );
+ return( -1 );
+ }
+ p_input->stream.pp_programs[0]->b_is_ok = 0;
+ p_input->stream.p_selected_program =
+ p_input->stream.p_new_program = p_input->stream.pp_programs[0];
+
+ /* create our ES */
+ p_es = input_AddES( p_input,
+ p_input->stream.p_selected_program,
+ 1, /* id */
+ 0 );
+ if( !p_es )
+ {
+ vlc_mutex_unlock( &p_input->stream.stream_lock );
+ intf_ErrMsg( "input error: not enough memory." );
+ return( -1 );
+ }
+ p_es->i_stream_id = 1;
+ p_es->i_type = !mpeg.i_layer ? MPEG1_AUDIO_ES : MPEG2_AUDIO_ES;
+ p_es->i_cat = AUDIO_ES;
+ p_es->b_audio = 1;
+ input_SelectES( p_input, p_es );
+
+ p_input->stream.p_selected_program->b_is_ok = 1;
+ vlc_mutex_unlock( &p_input->stream.stream_lock );
+
+ /* create p_mpegaudio and init it */
+ p_input->p_demux_data =
+ p_mpegaudio = malloc( sizeof( demux_data_mpegaudio_t ));
+
+ if( !p_mpegaudio )
+ {
+ intf_ErrMsg( "input error: not enough memory." );
+ return( -1 );
+ }
+
+ /*input_ClockInit( p_input->stream.p_selected_program );
+ done by AddProgram */
+ p_mpegaudio->p_es = p_es;
+ p_mpegaudio->mpeg = mpeg;
+ p_mpegaudio->i_framecount = 0;
+ p_mpegaudio->i_pts = 0;
+
+ /* parse Xing Header if present */
+ MPEGAudio_ExtractXingHeader( p_input, &p_mpegaudio->xingheader );
+
+ vlc_mutex_lock( &p_input->stream.stream_lock );
+ p_input->stream.i_mux_rate = p_mpegaudio->xingheader.i_avgbitrate / 50 / 8;
+ vlc_mutex_unlock( &p_input->stream.stream_lock );
+
+ /* FIXME FIXME FIXME FIXME FIXME FIXME FIXME */
+ /* if i don't do that, it don't work correctly but why ??? */
+ if( p_input->stream.b_seekable )
+ {
+ p_input->pf_seek( p_input, 0 );
+ input_AccessReinit( p_input );
+ }
+ /* FIXME FIXME FIXME FIXME FIXME FIXME FIXME */
+
+ /* all is ok :)) */
+ intf_Msg( "input init: Audio MPEG-%d layer %d %s %dHz %dKb/s %s",
+ mpeg.i_version + 1,
+ mpeg.i_layer +1 ,
+ mpegaudio_mode[mpeg.i_mode],
+ mpeg.i_samplingfreq,
+ p_mpegaudio->xingheader.i_avgbitrate / 1000,
+ p_mpegaudio->xingheader.i_flags ?
+ "VBR (Xing)" : ""
+ );
+ return( 0 );
+}
+
+
+/*****************************************************************************
+ * MPEGAudioEnd: frees unused data
+ *****************************************************************************/
+static void MPEGAudioEnd( input_thread_t * p_input )
+{
+
+}
+
+
+/*****************************************************************************
+ * MPEGAudioDemux: reads and demuxes data packets
+ *****************************************************************************
+ * Returns -1 in case of error, 0 in case of EOF, 1 otherwise
+ *****************************************************************************/
+static int MPEGAudioDemux( input_thread_t * p_input )
+{
+ int i_pos;
+ int i_toread;
+ pes_packet_t *p_pes;
+ mpegaudio_format_t mpeg;
+ demux_data_mpegaudio_t *p_mpegaudio =
+ (demux_data_mpegaudio_t*) p_input->p_demux_data;
+
+ /* look for a frame */
+ if( !MPEGAudio_FindFrame( p_input, &i_pos, &mpeg ) )
+ {
+ intf_WarnMsg( 1, "input error: cannot found next frame");
+ return( 0 );
+ }
+
+ /* if stream has changed */
+ if( ( mpeg.i_version != p_mpegaudio->mpeg.i_version )
+ ||( mpeg.i_layer != p_mpegaudio->mpeg.i_layer )
+ ||( mpeg.i_samplingfreq != p_mpegaudio->mpeg.i_samplingfreq ) )
+ {
+ intf_WarnMsg( 1, "input demux: stream has changed" );
+ p_mpegaudio->i_framecount = 0;
+ p_mpegaudio->i_pts = 0;
+ }
+
+ input_ClockManageRef( p_input,
+ p_input->stream.p_selected_program,
+ p_mpegaudio->i_pts );
+
+ /* in fact i_pos may be garbage but ... i don't want to skip it
+ it's borring ;) */
+
+ i_toread = MPEGAudio_FrameSize( &mpeg ) + i_pos;
+ /* create one pes */
+ if( !(p_pes = input_NewPES( p_input->p_method_data )) )
+ {
+ intf_ErrMsg( "input demux: out of memory" );
+ return( -1 );
+ }
+
+ while( i_toread > 0 )
+ {
+ data_packet_t *p_data;
+ int i_read;
+
+ if( (i_read = input_SplitBuffer( p_input, &p_data, i_toread ) ) <= 0 )
+ {
+ break;
+ }
+ if( !p_pes->p_first )
+ {
+ p_pes->p_first = p_data;
+ p_pes->i_nb_data = 1;
+ p_pes->i_pes_size = i_read;
+ }
+ else
+ {
+ p_pes->p_last->p_next = p_data;
+ p_pes->i_nb_data++;
+ p_pes->i_pes_size += i_read;
+ }
+ p_pes->p_last = p_data;
+ i_toread -= i_read;
+ }
+ /* XXX VERY STRANGE need to *90000 and not *1000000 WHYYYY ???
+ I know that for mpeg system clock unit is based on 90000 but
+ pts is not supposed to be in microsec for vlc ?
+ At least it's welcome to write it somewhere in input_clock.c
+ i've wasted time because of it :( */
+ p_mpegaudio->i_pts = (mtime_t)90000 *
+ (mtime_t)p_mpegaudio->i_framecount *
+ (mtime_t)MPEGAudio_DecodedFrameSize( &mpeg ) /
+ (mtime_t)mpeg.i_samplingfreq;
+ p_pes->i_dts = 0;
+ p_pes->i_pts = input_ClockGetTS( p_input,
+ p_input->stream.p_selected_program,
+ p_mpegaudio->i_pts );
+
+ if( !p_mpegaudio->p_es->p_decoder_fifo )
+ {
+ intf_ErrMsg( "input demux: no audio decoder" );
+ input_DeletePES( p_input->p_method_data, p_pes );
+ return( -1 ); /* perhaps not, it's my choice */
+ }
+ else
+ {
+ input_DecodePES( p_mpegaudio->p_es->p_decoder_fifo, p_pes );
+ }
+
+ p_mpegaudio->i_framecount++;
+ p_mpegaudio->mpeg = mpeg;
+
+ return( 1 );
+}
+
+
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