[vlc-devel] [PATCH] Adding caf file demuxer module.
Matthias Keiser
matthias at tristan-inc.com
Thu Sep 19 01:56:36 CEST 2013
From: Matthias Keiser <info at tristan-inc.com>
---
modules/demux/Modules.am | 2 +
modules/demux/caf.c | 887 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 889 insertions(+)
create mode 100644 modules/demux/caf.c
diff --git a/modules/demux/Modules.am b/modules/demux/Modules.am
index 8aed5d2..491fb5d 100644
--- a/modules/demux/Modules.am
+++ b/modules/demux/Modules.am
@@ -30,6 +30,7 @@ SOURCES_sid = sid.cpp
SOURCES_dirac = dirac.c
SOURCES_image = image.c mxpeg_helper.h
SOURCES_demux_stl = stl.c
+SOURCES_caf = caf.c
libasf_plugin_la_SOURCES = asf/asf.c asf/libasf.c asf/libasf.h asf/libasf_guid.h
libasf_plugin_la_CFLAGS = $(AM_CFLAGS)
@@ -199,6 +200,7 @@ libvlc_LTLIBRARIES += \
libxa_plugin.la \
libimage_plugin.la \
libdemux_stl_plugin.la \
+ libcaf_plugin.la \
$(NULL)
BUILT_SOURCES += dummy.cpp
diff --git a/modules/demux/caf.c b/modules/demux/caf.c
new file mode 100644
index 0000000..7a371f6
--- /dev/null
+++ b/modules/demux/caf.c
@@ -0,0 +1,887 @@
+/*****************************************************************************
+ * caf.c: Core Audio File Format demuxer
+ *****************************************************************************
+ * Copyright (C) 2013 VLC authors and VideoLAN
+ * $Id$
+ *
+ * Authors: Matthias Keiser <matthias at tristan-inc.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser 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_demux.h>
+#include <vlc_codecs.h>
+
+/*****************************************************************************
+ * Module descriptor
+ *****************************************************************************/
+static int Open ( vlc_object_t * );
+static void Close ( vlc_object_t * );
+
+vlc_module_begin ()
+set_category( CAT_INPUT )
+set_subcategory( SUBCAT_INPUT_DEMUX )
+set_description( N_("CAF demuxer" ) )
+set_capability( "demux", 1000 )
+set_callbacks( Open, Close )
+add_shortcut( "caf" )
+vlc_module_end ()
+
+/*****************************************************************************
+ * Local prototypes
+ *****************************************************************************/
+static int Demux ( demux_t * );
+static int Control( demux_t *, int i_query, va_list args );
+
+typedef struct frame_span_t
+{
+ int64_t i_frames;
+ int64_t i_samples;
+ int64_t i_bytes;
+ int64_t i_desc_bytes;
+} frame_span_t;
+
+typedef struct packet_table_t
+{
+ int64_t i_num_packets;
+ int64_t i_num_valid_frames;
+ int32_t i_num_priming_frames;
+ int32_t i_num_remainder_frames;
+ int64_t i_descriptions_start;
+} packet_table_t;
+
+struct demux_sys_t
+{
+ es_format_t fmt;
+ es_out_id_t *es;
+
+ int64_t i_data_offset;
+ int64_t i_data_size;
+
+ uint32_t i_unpacked_bits;
+
+ frame_span_t position;
+ packet_table_t packet_table;
+};
+
+static inline void FrameSpanAddSpan(frame_span_t *span1, frame_span_t *span2);
+static int FrameSpanAddDescription( demux_t *p_demux, uint64_t i_desc_offset, frame_span_t *span );
+static inline mtime_t FrameSpanGetTime( frame_span_t *span, uint32_t i_sample_rate);
+static int SetSpanWithSample(demux_t *p_demux, frame_span_t *span, int64_t i_target_sample);
+
+static int NextChunk( demux_t *p_demux, vlc_fourcc_t *p_fcc, int64_t *pi_size );
+static int ParseVarLenInteger(const uint8_t *p_buff, uint64_t i_buff_len, uint64_t *pi_value_out, int32_t *i_len_out );
+static inline double GetDBLBE(const uint8_t *p);
+static inline bool NeedsPacketTable(demux_sys_t *p_sys);
+static inline bool IsCompressed(demux_sys_t *p_sys);
+static int64_t TotalNumFrames( demux_t *p_demux );
+static int64_t TotalNumSamples( demux_t *p_demux );
+
+/*****************************************************************************
+ * Open
+ *****************************************************************************/
+static int Open( vlc_object_t *p_this )
+{
+ demux_t *p_demux = (demux_t*)p_this;
+ demux_sys_t *p_sys;
+
+ const uint8_t *p_peek;
+
+ if( stream_Peek( p_demux->s, &p_peek, 8 ) < 8 )
+ return VLC_EGENERIC;
+
+ /* Is it a caf file? */
+ if( memcmp( p_peek, "caff", 4 ))
+ return VLC_EGENERIC;
+
+ /* check file version (we only handle version 1) */
+ if( GetWBE( p_peek + 4 ) != 1 )
+ {
+ msg_Dbg(p_demux, "Unknown caf file version.");
+ return VLC_EGENERIC;
+ }
+
+ /* check file flags (must be 0) */
+ if( GetWBE( p_peek + 6 ) != 0 )
+ {
+ msg_Dbg( p_demux, "Unknown caf file flags." );
+ return VLC_EGENERIC;
+ }
+
+ if( stream_Read( p_demux->s, NULL, 8) < 8 )
+ return VLC_EGENERIC; /* This would be very strange since we justed peeked at these bytes. */
+
+ DEMUX_INIT_COMMON();
+ p_sys = p_demux->p_sys;
+ es_format_Init( &p_sys->fmt, UNKNOWN_ES, 0 );
+
+ vlc_fourcc_t i_fcc;
+ int64_t i_size;
+ int64_t i_idx = 0;
+
+ while( NextChunk( p_demux, &i_fcc, &i_size ) == VLC_SUCCESS )
+ {
+ if( i_fcc == 'desc' )
+ {
+
+ msg_Dbg( p_demux, "Found 'desc' chunk." );
+
+ if( i_idx != 0 )
+ msg_Warn( p_demux, "The audio description chunk must be the first chunk in a caf file. Continuing anyways." );
+
+ if ( stream_Peek( p_demux->s, &p_peek, 8 + 6 * 4 ) < ( 8 + 6 * 4) ) {
+ goto error;
+ }
+
+ vlc_fourcc_t i_fmt = GetDWBE( p_peek + 8 );
+ uint32_t i_fmt_flags = GetDWBE( p_peek + 12 );
+
+ uint32_t i_bits_per_channel = GetDWBE( p_peek + 28 );
+ uint32_t i_bytes_per_packet = GetDWBE( p_peek + 16 );
+ uint32_t i_frames_per_packet = GetDWBE( p_peek + 20 );
+ uint32_t i_channels_per_frame = GetDWBE( p_peek + 24 );
+ uint32_t i_unpacked_bits_per_sample = ( i_bytes_per_packet / i_frames_per_packet / i_channels_per_frame ) * 8;
+
+ if( i_fmt == 'lpcm') {
+
+ bool b_is_float = !!( i_fmt_flags & ( 1 << 0 ) );
+ bool b_is_be = !( i_fmt_flags & ( 1 << 1 ) );
+
+ vlc_fourcc_t i_basic_codec = 0;
+
+ if( !b_is_float )
+ {
+
+ i_basic_codec = b_is_be ? VLC_FOURCC( 't', 'w', 'o', 's' ) : VLC_FOURCC( 's', 'o', 'w', 't' );
+ es_format_Init( &p_sys->fmt, AUDIO_ES, vlc_fourcc_GetCodecAudio( i_basic_codec, i_unpacked_bits_per_sample ));
+ }
+ else
+ {
+ if( i_bits_per_channel == 32 )
+ i_basic_codec = b_is_be ? VLC_CODEC_F32B : VLC_CODEC_F32L;
+ else if( i_bits_per_channel == 64 )
+ i_basic_codec = b_is_be ? VLC_CODEC_F64B : VLC_CODEC_F64L;
+
+ if( i_basic_codec )
+ es_format_Init( &p_sys->fmt, AUDIO_ES, vlc_fourcc_GetCodecAudio( i_basic_codec, i_bits_per_channel ));
+ }
+ }
+ else if( i_fmt == 'aac ' )
+ {
+ int kMP4Audio_AAC_LC_ObjectType = 2;
+
+ if( i_fmt_flags != kMP4Audio_AAC_LC_ObjectType )
+ {
+ msg_Warn( p_demux, "The only documented format flag for aac is 2 (kMP4Audio_AAC_LC_ObjectType), but is %i. Continuing anyways.", i_fmt_flags );
+ }
+
+ es_format_Init( &p_sys->fmt, AUDIO_ES, vlc_fourcc_GetCodecAudio( VLC_CODEC_MP4A, 0 ));
+
+ }
+ else
+ {
+ es_format_Init( &p_sys->fmt, AUDIO_ES, vlc_fourcc_GetCodecAudio( hton32( i_fmt ), 0 ));
+ }
+
+ if( !p_sys->fmt.i_codec )
+ {
+ msg_Err( p_demux, "could not determine codec" );
+ goto error;
+ }
+
+ p_sys->fmt.audio.i_rate = (unsigned int)GetDBLBE( p_peek );
+ p_sys->fmt.audio.i_channels = i_channels_per_frame;
+ p_sys->fmt.audio.i_bytes_per_frame = i_bytes_per_packet; /* "mBytesPerPacket" in Apple parlance */
+ p_sys->fmt.audio.i_frame_length = i_frames_per_packet; /* "mFramesPerPacket" in Apple parlance */
+ p_sys->fmt.audio.i_bitspersample = i_bits_per_channel; /* mBitsPerChannel */
+ p_sys->fmt.audio.i_blockalign = i_bytes_per_packet;
+ p_sys->fmt.i_bitrate = i_bits_per_channel * p_sys->fmt.audio.i_rate * i_channels_per_frame;
+ p_sys->i_unpacked_bits = i_unpacked_bits_per_sample;
+
+ }
+ else if( i_fcc == 'data' )
+ {
+ msg_Dbg( p_demux, "Found 'data' chunk." );
+
+ p_sys->i_data_offset = stream_Tell( p_demux->s ) + 4; /* skip edit count */
+ p_sys->i_data_size = i_size < 0 ? -1 : ( i_size - 4 );
+ }
+ else if( i_fcc == 'pakt' )
+ {
+ msg_Dbg( p_demux, "Found 'pakt' chunk." );
+
+ if ( stream_Peek( p_demux->s, &p_peek, 8 + 8 + 4 + 4 ) < ( 8 + 8 + 4 + 4 ))
+ {
+ msg_Err(p_demux, "Couldn't peek packet descriptions");
+ goto error;
+ }
+
+ p_sys->packet_table.i_num_packets = GetQWBE( p_peek );
+ p_sys->packet_table.i_num_valid_frames = GetQWBE( p_peek + 8 );
+ p_sys->packet_table.i_num_priming_frames = GetDWBE(p_peek + 16 );
+ p_sys->packet_table.i_num_remainder_frames = GetDWBE(p_peek + 20 );
+ p_sys->packet_table.i_descriptions_start = stream_Tell( p_demux->s ) + 24;
+ }
+ else if( i_fcc == 'kuki' )
+ {
+ msg_Dbg( p_demux, "Found 'kuki' chunk." );
+
+ if( stream_Peek( p_demux->s, &p_peek, (int)i_size ) < i_size )
+ {
+ msg_Err(p_demux, "Couldn't peek extra data");
+ goto error;
+ }
+
+ #define P_EXTRA ((char *)p_sys->fmt.p_extra) /* Avoid pointer arithmetic warnings. */
+
+ if( p_sys->fmt.i_codec == VLC_CODEC_ALAC )
+ {
+ /*
+ HACK! No idea what I'm really doing here, this is lifted from cafdec.c libavformat.
+ In an ideal world this would be part of the relevant codec module, because we don't
+ care about any of this at the demuxer level.
+ */
+
+ int kALAC_NEW_KUKI_SIZE = 24;
+ int kALAC_LIB_REQ_KUKI_SIZE = 36;
+ int i_extra;
+
+ if( i_size == kALAC_NEW_KUKI_SIZE || i_size == kALAC_LIB_REQ_KUKI_SIZE )
+ {
+ i_extra = kALAC_LIB_REQ_KUKI_SIZE;
+ }
+ else
+ {
+ msg_Err(p_demux, "Unknown alac magic cookie. Passing it on to the decoder as is and hoping for the best." );
+ i_extra = (int)i_size;
+ }
+
+ p_sys->fmt.i_extra = i_extra;
+ p_sys->fmt.p_extra = malloc( i_extra );
+
+ if( !p_sys->fmt.p_extra )
+ {
+ msg_Err(p_demux, "Could not allocate extra information." );
+ goto error;
+ }
+
+ if( i_size == kALAC_NEW_KUKI_SIZE ) {
+
+ SetDWBE( P_EXTRA, 36 );
+ memcpy( P_EXTRA + 4, "alac", 4 );
+ SetDWBE( P_EXTRA + 8, 0 );
+ memcpy( P_EXTRA + 12, p_peek, 24 );
+ }
+ else
+ {
+ memcpy( p_sys->fmt.p_extra, p_peek, i_size );
+ }
+ }
+ else if( p_sys->fmt.i_codec == VLC_CODEC_MP4A )
+ {
+
+ /*
+ HACK! No idea what I'm really doing here, this is lifted from libmp4.c in the mp4 demuxer module.
+ In an ideal world this would be part of the relevant codec module, because we don't
+ care about any of this at the demuxer level.
+ */
+
+
+ #define AAC_GET_TAG do { \
+ if( i_offset + 1 <= i_size ) \
+ { \
+ i_tag = *( p_peek + i_offset++ ); \
+ } \
+ else \
+ { \
+ goto aac_kuki_finish; \
+ } \
+ } while(0)
+
+ #define AAC_CHECK_LEN(length) do { \
+ if( i_offset + length > i_size ) \
+ { \
+ goto aac_kuki_finish; \
+ } \
+ } while(0)
+
+ #define AAC_GET_TAG_LENGTH do { \
+ if( ParseVarLenInteger( p_peek + i_offset, i_size - i_offset, &i_tag_size, &i_int_size )) \
+ { \
+ goto aac_kuki_finish; \
+ } \
+ i_offset += i_int_size; \
+ } while(0)
+
+ const uint8_t kAAC_ES_DESCR_TAG = 3;
+ const uint8_t kAAC_DEC_CONFIG_DESCR_TAG = 4;
+ const uint8_t kAAC_DEC_SPEC_INFO_TAG = 5;
+
+ int64_t i_offset = 0;
+ int64_t i_kuki_size = 0;
+ uint64_t i_tag_size;
+ int32_t i_int_size;
+ uint8_t i_tag;
+
+ AAC_GET_TAG;
+
+ if( i_tag == kAAC_ES_DESCR_TAG )
+ {
+
+ AAC_GET_TAG_LENGTH;
+
+ AAC_CHECK_LEN(3);
+ i_offset += 2; /* don't care (ES ID) */
+ uint8_t i_flags = *(p_peek + i_offset++ );
+
+ if( i_flags&0x80 )
+ {
+ AAC_CHECK_LEN(2);
+ i_offset += 2; /* don't care (dependance) */
+ }
+ if( i_flags&0x40 )
+ {
+ AAC_CHECK_LEN(1);
+ uint8_t i_url_len = *( p_peek + i_offset++ );
+ i_offset += i_url_len; /* don't care (url) */
+ }
+ if( i_flags&0x20 )
+ {
+ AAC_CHECK_LEN(2);
+ i_offset += 2; /* don't care (OCR) */
+ }
+
+ AAC_GET_TAG;
+ }
+ if( i_tag != kAAC_DEC_CONFIG_DESCR_TAG )
+ goto aac_kuki_finish;
+
+ AAC_GET_TAG_LENGTH;
+
+ AAC_CHECK_LEN( 1 + 1 + 3 + 4 + 4);
+ i_offset += ( 1 + 1 + 3 + 4 + 4 ); /* don't care */
+
+ AAC_GET_TAG;
+
+ if( i_tag != kAAC_DEC_SPEC_INFO_TAG ) /* this is the one we need */
+ goto aac_kuki_finish;
+
+ AAC_GET_TAG_LENGTH;
+
+ if( i_offset + i_tag_size > i_size )
+ goto aac_kuki_finish;
+
+ i_kuki_size = i_tag_size;
+
+ aac_kuki_finish:
+
+ if( !i_kuki_size)
+ {
+ msg_Warn(p_demux, "Error parsing aac cookie. Passing it on to the decoder as is and hoping for the best.");
+ i_kuki_size = i_size;
+ i_offset = 0;
+ }
+
+ p_sys->fmt.i_extra = (int)i_kuki_size;
+ p_sys->fmt.p_extra = malloc(i_kuki_size);
+
+ if( !p_sys->fmt.p_extra )
+ {
+ msg_Err(p_demux, "Could not allocate extra information." );
+ goto error;
+ }
+
+ memcpy( p_sys->fmt.p_extra, p_peek + i_offset, i_kuki_size );
+ }
+ else
+ {
+ p_sys->fmt.i_extra = (int)i_size;
+ p_sys->fmt.p_extra = malloc(i_size);
+
+ if( !p_sys->fmt.p_extra )
+ {
+ msg_Err(p_demux, "Could not allocate extra information." );
+ goto error;
+ }
+ memcpy(p_sys->fmt.p_extra, p_peek, p_sys->fmt.i_extra);
+ }
+ }
+ else
+ {
+ vlc_fourcc_t i_fcc_be = hton32( i_fcc );
+ msg_Dbg( p_demux, "Ignoring '%4.4s' chunk.", ( char * )&i_fcc_be );
+ }
+
+ if( i_size == -1 )
+ break;
+
+ if( stream_Seek( p_demux->s, stream_Tell( p_demux->s ) + i_size ) != VLC_SUCCESS )
+ break;
+
+ i_idx++;
+ }
+
+ if ( !p_sys->i_data_offset || p_sys->fmt.i_cat != AUDIO_ES ||
+ ( NeedsPacketTable( p_sys ) && !p_sys->packet_table.i_descriptions_start ))
+ {
+ msg_Err( p_demux, "Did not find all necessary chunks." );
+ goto error;
+ }
+
+ p_sys->es = es_out_Add( p_demux->out, &p_sys->fmt );
+
+ return VLC_SUCCESS;
+
+error:
+ free( p_sys );
+ return VLC_EGENERIC;
+}
+
+/*****************************************************************************
+ * Demux:
+ *****************************************************************************/
+static int Demux( demux_t *p_demux )
+{
+ demux_sys_t *p_sys = p_demux->p_sys;
+ block_t *p_block;
+
+ if( p_sys->i_data_size != -1 && p_sys->position.i_bytes >= p_sys->i_data_size )
+ {
+ /* EOF */
+ return 0;
+ }
+
+ frame_span_t advance = {0};
+
+ /* we will read 50ms at once */
+ uint64_t i_req_samples = ( __MAX( p_sys->fmt.audio.i_rate / 20, 1 ));
+
+ if( !NeedsPacketTable(p_sys) ) /* PCM/IMA4 */
+ {
+ uint64_t i_req_frames = ( i_req_samples + ( p_sys->fmt.audio.i_frame_length - 1 )) / p_sys->fmt.audio.i_frame_length;
+
+ if( p_sys->i_data_size != -1 && ( p_sys->position.i_bytes + i_req_frames * p_sys->fmt.audio.i_bytes_per_frame ) > p_sys->i_data_size )
+ {
+ i_req_frames = ( p_sys->i_data_size - p_sys->position.i_frames * p_sys->fmt.audio.i_bytes_per_frame) / p_sys->fmt.audio.i_bytes_per_frame;
+ }
+
+ advance.i_frames = i_req_frames;
+ advance.i_samples = i_req_frames * p_sys->fmt.audio.i_frame_length;
+ advance.i_bytes = p_sys->fmt.audio.i_bytes_per_frame * advance.i_frames;
+ }
+ else /* use packet table */
+ {
+ do
+ {
+ if( FrameSpanAddDescription( p_demux, p_sys->position.i_desc_bytes + advance.i_desc_bytes, &advance ))
+ break;
+ }
+ while (( i_req_samples > advance.i_samples) && ( p_sys->position.i_frames + advance.i_frames ) < p_sys->packet_table.i_num_packets );
+ }
+
+ if( !advance.i_frames )
+ {
+ msg_Err(p_demux, "Unexpected end of file");
+ return -1;
+ }
+
+ if( stream_Seek( p_demux->s, p_sys->i_data_offset + p_sys->position.i_bytes ))
+ {
+ msg_Err( p_demux, "cannot seek data" );
+ return -1;
+ }
+
+ if( ( p_block = stream_Block(p_demux->s, ( int )advance.i_bytes )) == NULL )
+ {
+ msg_Err( p_demux, "cannot read data" );
+ return -1;
+ }
+
+ p_block->i_dts =
+ p_block->i_pts = VLC_TS_0 + FrameSpanGetTime( &p_sys->position, p_sys->fmt.audio.i_rate );
+
+ FrameSpanAddSpan(&p_sys->position, &advance);
+
+ /* set PCR */
+ es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block->i_pts );
+
+ es_out_Send( p_demux->out, p_sys->es, p_block );
+
+ return 1;
+}
+
+/*****************************************************************************
+ * Control:
+ *****************************************************************************/
+static int Control( demux_t *p_demux, int i_query, va_list args )
+{
+ int64_t i64, *pi64, i_sample;
+ double f, *pf;
+ frame_span_t position;
+
+ demux_sys_t *p_sys = p_demux->p_sys;
+ uint64_t i_num_samples = TotalNumSamples( p_demux );
+
+ switch( i_query ) {
+
+ case DEMUX_GET_LENGTH:
+ pi64 = ( int64_t* )va_arg( args, int64_t * );
+ *pi64 = INT64_C( 1000000 ) * ( i_num_samples / p_sys->fmt.audio.i_rate );
+ return VLC_SUCCESS;
+
+ case DEMUX_GET_TIME:
+ pi64 = ( int64_t* )va_arg( args, int64_t * );
+ *pi64 = INT64_C( 1000000 ) * ( p_sys->position.i_samples / p_sys->fmt.audio.i_rate );
+ return VLC_SUCCESS;
+
+ case DEMUX_GET_POSITION:
+ pf = (double*)va_arg( args, double * );
+ *pf = i_num_samples ? (double)p_sys->position.i_samples / (double)i_num_samples : 0.0;
+ return VLC_SUCCESS;
+
+ case DEMUX_SET_POSITION:
+ f = (double)va_arg( args, double );
+ i_sample = f * i_num_samples;
+ if( SetSpanWithSample( p_demux, &position, i_sample ))
+ return VLC_EGENERIC;
+ p_sys->position = position;
+ return VLC_SUCCESS;
+
+ case DEMUX_SET_TIME:
+ i64 = (int64_t)va_arg( args, int64_t );
+ i_sample = i64 * p_sys->fmt.audio.i_rate / INT64_C(1000000);
+ if( SetSpanWithSample( p_demux, &position, i_sample ))
+ return VLC_EGENERIC;
+ p_sys->position = position;
+ return VLC_SUCCESS;
+
+ case DEMUX_GET_META:
+ return stream_Control( p_demux->s, STREAM_GET_META, args );
+
+ default:
+ return VLC_EGENERIC;
+ }
+
+ return VLC_EGENERIC;
+}
+
+
+/*****************************************************************************
+ * Close
+ *****************************************************************************/
+static void Close( vlc_object_t *p_this )
+{
+ demux_t *p_demux = (demux_t*)p_this;
+ demux_sys_t *p_sys = p_demux->p_sys;
+
+ free(p_sys->fmt.p_extra);
+ free( p_sys );
+}
+
+/***************************** Local Functions *******************************/
+
+
+/*****************************************************************************
+ * FrameSpan Functions
+ *****************************************************************************
+ * A FrameSpan structure contains the relationship between a number of
+ frames, the number of samples they contain, the amount of data they
+ use, and the length of their packet descriptions (if any).
+ *****************************************************************************/
+
+/* FrameSpanAddSpan adds span2 to span1 */
+
+static inline void FrameSpanAddSpan( frame_span_t *span1, frame_span_t *span2 )
+{
+ span1->i_frames += span2->i_frames;
+ span1->i_samples += span2->i_samples;
+ span1->i_bytes += span2->i_bytes;
+ span1->i_desc_bytes += span2->i_desc_bytes;
+}
+
+/* Adds the frame that is described at i_desc_offset to span */
+
+static int FrameSpanAddDescription( demux_t *p_demux, uint64_t i_desc_offset, frame_span_t *span )
+{
+ demux_sys_t *p_sys = p_demux->p_sys;
+
+ /* Avoid seeking + peeking for simple case (PCM) */
+ if( p_sys->fmt.audio.i_bytes_per_frame && p_sys->fmt.audio.i_frame_length )
+ {
+ span->i_bytes += p_sys->fmt.audio.i_bytes_per_frame;
+ span->i_samples += p_sys->fmt.audio.i_frame_length;
+ span->i_frames++;
+ return VLC_SUCCESS;
+ }
+
+ uint32_t i_desc_size = 0;
+
+ if( stream_Seek( p_demux->s, p_sys->packet_table.i_descriptions_start + i_desc_offset ))
+ {
+ msg_Err(p_demux, "Couldn't seek packet description.");
+ return VLC_EGENERIC;
+ }
+
+ const uint8_t *p_peek;
+ uint32_t i_peek_len = stream_Peek( p_demux->s, &p_peek, 2 * 10 ); /* Peeking the maximum number of bytes that two 64 bit numbers could use (( 64 + 6 ) / 7 = 10 ). */
+
+ if( p_sys->fmt.audio.i_bytes_per_frame )
+ {
+ span->i_bytes += p_sys->fmt.audio.i_bytes_per_frame;
+ }
+ else
+ {
+ uint64_t i_size;
+ int32_t i_this_int;
+ if( ParseVarLenInteger( p_peek, i_peek_len, &i_size, &i_this_int ))
+ {
+ return VLC_EGENERIC;
+ }
+
+ i_desc_size += i_this_int;
+ span->i_bytes += i_size;
+ }
+
+ if( p_sys->fmt.audio.i_frame_length)
+ {
+ span->i_samples += p_sys->fmt.audio.i_frame_length;
+ }
+ else
+ {
+ if( i_desc_size >= i_peek_len )
+ {
+ return VLC_EGENERIC;
+ }
+
+ uint64_t i_num_samples;
+ int32_t i_this_int;
+ if( ParseVarLenInteger( p_peek + i_desc_size, i_peek_len - i_desc_size, &i_num_samples, &i_this_int ))
+ {
+ return VLC_EGENERIC;
+ }
+
+ i_desc_size += i_this_int;
+ span->i_samples += i_num_samples;
+ }
+ span->i_desc_bytes += i_desc_size;
+ span->i_frames++;
+
+ return VLC_SUCCESS;
+}
+
+/* FrameSpanGetTime returns the time span represented by the frame span. */
+
+static inline mtime_t FrameSpanGetTime( frame_span_t *span, uint32_t i_sample_rate)
+{
+ date_t date;
+
+ date_Init( &date, ( uint32_t )i_sample_rate, 1 );
+ date_Set( &date, 1 );
+ date_Increment( &date, ( uint32_t )span->i_samples );
+
+ return date_Get( &date );
+}
+
+/* SetSpanWithSample returns the span from the beginning of the file up to and
+ including the specified sample. This works at frame granularity, so the
+ returned span may not represent the exact target sample.
+ Since we might have to lineraly search the packet descriptions, this is a
+ potentially slow operation! */
+
+static int SetSpanWithSample(demux_t *p_demux, frame_span_t *span, int64_t i_target_sample)
+{
+ demux_sys_t *p_sys = p_demux->p_sys;
+
+ int64_t i_num_frames = TotalNumFrames( p_demux );
+
+ if( !NeedsPacketTable( p_sys ))
+ {
+ int64_t i_frame = i_target_sample / p_sys->fmt.audio.i_frame_length;
+ int64_t i_remaining = i_target_sample - i_frame * p_sys->fmt.audio.i_frame_length;
+ if( i_remaining > ( p_sys->fmt.audio.i_frame_length / 2 ))
+ i_frame++;
+
+ if( i_frame > i_num_frames)
+ i_frame = i_num_frames;
+
+ span->i_frames = i_frame;
+ span->i_samples = i_frame * p_sys->fmt.audio.i_frame_length;
+ span->i_bytes = i_frame * p_sys->fmt.audio.i_bytes_per_frame;
+ span->i_desc_bytes = 0;
+ }
+ else {
+
+ memset(span, 0, sizeof( frame_span_t ));
+ frame_span_t prev_span;
+
+ while( span->i_samples < i_target_sample && span->i_frames < i_num_frames ) {
+
+ prev_span = *span;
+
+ if( FrameSpanAddDescription( p_demux, span->i_desc_bytes, span ))
+ return VLC_EGENERIC;
+
+ if( span->i_samples >= i_target_sample )
+ {
+ int64_t i_this_samples = span->i_samples - prev_span.i_samples;
+
+ if( i_target_sample - prev_span.i_samples < i_this_samples / 2 )
+ *span = prev_span;
+
+ break;
+ }
+ }
+ }
+
+ return VLC_SUCCESS;
+}
+
+/*****************************************************************************
+ * Various Utility Functions
+ *****************************************************************************/
+
+/* The NextChunk function returns the four char code and the size at the current file position.
+ Upon return the file position points to the start of the chunk payload. */
+
+static int NextChunk( demux_t *p_demux, vlc_fourcc_t *p_fcc, int64_t *pi_size )
+{
+ const uint8_t *p_peek;
+
+ if( stream_Peek( p_demux->s, &p_peek, 12 ) < 12 )
+ return VLC_EGENERIC;
+
+ *p_fcc = GetDWBE(p_peek);
+ *pi_size = GetQWBE(p_peek + 4);
+
+ if( stream_Read( p_demux->s, NULL, 12 ) < 12 )
+ return VLC_EGENERIC;
+
+ return VLC_SUCCESS;
+
+}
+
+/* ParseVarLenInteger parses a var length integer as found in the packet descriptions
+ (and in the aac magic cookie). In theorie a var length integer could be bigger than
+ an uint64_t, but I think it's unlikely to ever be a problem... */
+
+static int ParseVarLenInteger(const uint8_t *p_buff, uint64_t i_buff_len, uint64_t *pi_value_out, int32_t *i_len_out )
+{
+ *i_len_out = 0;
+
+ uint64_t i_value = 0;
+ bool finished = false;
+
+ for( uint32_t i = 0; i < i_buff_len; i++)
+ {
+ uint8_t i_byte = p_buff[i];
+ i_value = ( i_value << 7 ) | ( i_byte & 0x7f );
+
+ ( *i_len_out )++;
+
+ if( !( i_byte & 0x80 ))
+ {
+ finished = true;
+ break;
+ }
+ }
+
+ if( !finished )
+ {
+ return VLC_EGENERIC;
+ }
+
+ *pi_value_out = i_value;
+
+ return VLC_SUCCESS;
+}
+
+/* Utility function that reads a big endian double from the input buffer. */
+
+static inline double GetDBLBE(const uint8_t *p)
+{
+ uint64_t i_mem = GetQWBE(p);
+ return *(double *)(&i_mem);
+}
+
+static inline bool NeedsPacketTable(demux_sys_t *p_sys)
+{
+ return ( !p_sys->fmt.audio.i_bytes_per_frame || !p_sys->fmt.audio.i_frame_length);
+}
+
+static inline bool IsCompressed(demux_sys_t *p_sys)
+{
+ return !p_sys->fmt.audio.i_bitspersample;
+}
+
+static int64_t TotalNumFrames( demux_t *p_demux )
+{
+ demux_sys_t *p_sys = p_demux->p_sys;
+
+ int64_t i_num_frames;
+
+ if( !NeedsPacketTable( p_sys ))
+ {
+ int64_t i_data_size;
+
+ if( p_sys->i_data_size >= 0 )
+ {
+ i_data_size = p_sys->i_data_size;
+ }
+ else
+ {
+ i_data_size = stream_Size( p_demux->s ) - p_sys->i_data_offset;
+ }
+
+ if( i_data_size <= 0 )
+ return 0;
+
+ i_num_frames = i_data_size / p_sys->fmt.audio.i_bytes_per_frame;
+ }
+ else
+ {
+ i_num_frames = p_sys->packet_table.i_num_packets;
+ }
+
+ return i_num_frames;
+}
+
+static int64_t TotalNumSamples( demux_t *p_demux )
+{
+ demux_sys_t *p_sys = p_demux->p_sys;
+
+ int64_t i_num_samples;
+
+ if( !NeedsPacketTable( p_sys ))
+ {
+ i_num_samples = TotalNumFrames( p_demux ) * p_sys->fmt.audio.i_frame_length;
+ }
+ else
+ {
+ i_num_samples = p_sys->packet_table.i_num_valid_frames + p_sys->packet_table.i_num_priming_frames + p_sys->packet_table.i_num_remainder_frames;
+ }
+
+ return i_num_samples;
+}
+
--
1.7.12.4 (Apple Git-37)
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