/***************************************************************************** * xa.c : xa file demux module for vlc ***************************************************************************** * Copyright (C) 2005 Rémi Denis-Courmont * $Id$ * * Authors: Rémi Denis-Courmont * * 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 #include #include #include /***************************************************************************** * Module descriptor *****************************************************************************/ static int Open ( vlc_object_t * ); static void Close( vlc_object_t * ); vlc_module_begin () set_description( N_("XA demuxer") ) set_category( CAT_INPUT ) set_subcategory( SUBCAT_INPUT_DEMUX ) set_capability( "demux", 10 ) set_callbacks( Open, Close ) vlc_module_end () /***************************************************************************** * Local prototypes *****************************************************************************/ static int Demux ( demux_t * ); static int Control( demux_t *, int i_query, va_list args ); struct demux_sys_t { es_out_id_t *p_es; unsigned int i_data_size; unsigned int i_block_frames; unsigned int i_frame_size; unsigned int i_bitrate; date_t pts; }; typedef struct xa_header_t { char xa_id[4]; uint32_t iSize; uint16_t wFormatTag; uint16_t nChannels; uint32_t nSamplesPerSec; uint32_t nAvgBytesPerSec; uint16_t nBlockAlign; uint16_t wBitsPerSample; } xa_header_t; #define HEADER_LENGTH 24 static_assert(offsetof(xa_header_t, wBitsPerSample) == 22, "Bad padding"); #define FRAME_LENGTH 28 /* samples per frame */ /***************************************************************************** * Open: check file and initializes structures *****************************************************************************/ static int Open( vlc_object_t * p_this ) { demux_t *p_demux = (demux_t*)p_this; const uint8_t *peek; /* XA file heuristic */ if( vlc_stream_Peek( p_demux->s, &peek, 10 ) < 10 ) return VLC_EGENERIC; if( memcmp( peek, "XAI", 4 ) && memcmp( peek, "XAJ", 4 ) && memcmp( peek, "XA\0", 4 ) ) return VLC_EGENERIC; if( GetWLE( peek + 8 ) != 1 ) /* format tag */ return VLC_EGENERIC; demux_sys_t *p_sys = malloc( sizeof( demux_sys_t ) ); if( unlikely( p_sys == NULL ) ) return VLC_ENOMEM; /* read XA header*/ xa_header_t xa; if( vlc_stream_Read( p_demux->s, &xa, HEADER_LENGTH ) < HEADER_LENGTH ) { free( p_sys ); return VLC_EGENERIC; } es_format_t fmt; es_format_Init( &fmt, AUDIO_ES, VLC_CODEC_ADPCM_XA_EA ); msg_Dbg( p_demux, "assuming EA ADPCM audio codec" ); fmt.audio.i_rate = GetDWLE( &xa.nSamplesPerSec ); fmt.audio.i_bytes_per_frame = 15 * GetWLE( &xa.nChannels ); fmt.audio.i_frame_length = FRAME_LENGTH; fmt.audio.i_channels = GetWLE ( &xa.nChannels ); fmt.audio.i_blockalign = fmt.audio.i_bytes_per_frame; fmt.audio.i_bitspersample = GetWLE( &xa.wBitsPerSample ); fmt.i_bitrate = (fmt.audio.i_rate * fmt.audio.i_bytes_per_frame * 8) / fmt.audio.i_frame_length; /* FIXME: better computation */ p_sys->i_data_size = xa.iSize * 15 / 56; /* How many frames per block (1:1 is too CPU intensive) */ p_sys->i_block_frames = fmt.audio.i_rate / (FRAME_LENGTH * 20) + 1; p_sys->i_frame_size = fmt.audio.i_bytes_per_frame; p_sys->i_bitrate = fmt.i_bitrate; msg_Dbg( p_demux, "fourcc: %4.4s, channels: %d, " "freq: %d Hz, bitrate: %dKo/s, blockalign: %d", (char *)&fmt.i_codec, fmt.audio.i_channels, fmt.audio.i_rate, fmt.i_bitrate / 8192, fmt.audio.i_blockalign ); if( fmt.audio.i_rate == 0 || fmt.audio.i_channels == 0 || fmt.audio.i_bitspersample != 16 ) { free( p_sys ); return VLC_EGENERIC; } p_sys->p_es = es_out_Add( p_demux->out, &fmt ); date_Init( &p_sys->pts, fmt.audio.i_rate, 1 ); date_Set( &p_sys->pts, VLC_TICK_0 ); p_demux->pf_demux = Demux; p_demux->pf_control = Control; p_demux->p_sys = p_sys; return VLC_SUCCESS; } /***************************************************************************** * Demux: read packet and send them to decoders ***************************************************************************** * Returns -1 in case of error, 0 in case of EOF, 1 otherwise *****************************************************************************/ static int Demux( demux_t *p_demux ) { demux_sys_t *p_sys = p_demux->p_sys; block_t *p_block; int64_t i_offset = vlc_stream_Tell( p_demux->s ); unsigned i_frames = p_sys->i_block_frames; if( p_sys->i_data_size > 0 && (i_offset - HEADER_LENGTH) >= p_sys->i_data_size ) { /* EOF */ return 0; } p_block = vlc_stream_Block( p_demux->s, p_sys->i_frame_size * i_frames ); if( p_block == NULL ) { msg_Warn( p_demux, "cannot read data" ); return 0; } i_frames = p_block->i_buffer / p_sys->i_frame_size; p_block->i_dts = p_block->i_pts = date_Get( &p_sys->pts ); es_out_SetPCR( p_demux->out, p_block->i_pts ); es_out_Send( p_demux->out, p_sys->p_es, p_block ); date_Increment( &p_sys->pts, i_frames * FRAME_LENGTH ); return 1; } /***************************************************************************** * Close: frees unused data *****************************************************************************/ static void Close ( vlc_object_t * p_this ) { demux_sys_t *p_sys = ((demux_t *)p_this)->p_sys; free( p_sys ); } /***************************************************************************** * Control: *****************************************************************************/ static int Control( demux_t *p_demux, int i_query, va_list args ) { demux_sys_t *p_sys = p_demux->p_sys; return demux_vaControlHelper( p_demux->s, HEADER_LENGTH, p_sys->i_data_size ? (int64_t)HEADER_LENGTH + p_sys->i_data_size : -1, p_sys->i_bitrate, p_sys->i_frame_size, i_query, args ); }