Aegisub/aegisub/src/audio_provider_ffmpegsource.cpp

// Copyright (c) 2008, Karl Blomster
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
//   * Redistributions of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//   * Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//   * Neither the name of the Aegisub Group nor the names of its contributors
//     may be used to endorse or promote products derived from this software
//     without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// -----------------------------------------------------------------------------
//
// AEGISUB
//
// Website: http://aegisub.cellosoft.com
// Contact: mailto:zeratul@cellosoft.com
//

#include "config.h"

#ifdef WITH_FFMPEGSOURCE

///////////
// Headers
#include "include/aegisub/aegisub.h"
#include "audio_provider_ffmpegsource.h"
#ifdef WIN32
#include <objbase.h>
#endif


///////////
// Constructor
FFmpegSourceAudioProvider::FFmpegSourceAudioProvider(Aegisub::String filename) {
	COMInited = false;
#ifdef WIN32
	HRESULT res;
	res = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED);
	if (SUCCEEDED(res)) 
		COMInited = true;
	else if (res != RPC_E_CHANGED_MODE)
		throw _T("FFmpegSource video provider: COM initialization failure");
#endif
	FFMS_Init(0);

	MsgSize = sizeof(FFMSErrMsg);
	MsgString = _T("FFmpegSource audio provider: ");

	AudioSource = NULL;

	try {
		LoadAudio(filename);
	} catch (...) {
		Close();
		throw;
	}
}


///////////
// Load audio file
void FFmpegSourceAudioProvider::LoadAudio(Aegisub::String filename) {
	// clean up
	Close();

	wxString FileNameWX = wxFileName(wxString(filename.c_str(), wxConvFile)).GetShortPath();

	// generate a default name for the cache file
	wxString CacheName = GetCacheFilename(filename.c_str());

	FFIndex *Index = NULL;
	bool ReIndex = false;
	Index = FFMS_ReadIndex(CacheName.mb_str(wxConvUTF8), FFMSErrMsg, MsgSize);
	if (Index == NULL) {
		ReIndex = true;
	}
	// index exists, but is it the index we think it is?
	else if (FFMS_IndexBelongsToFile(Index, FileNameWX.mb_str(wxConvUTF8), FFMSErrMsg, MsgSize)) {
		FFMS_DestroyIndex(Index);
		Index = NULL;
		ReIndex = true;
	}
	// it is, but does it have indexing info for the audio track(s)?
	else {
		int NumTracks = FFMS_GetNumTracks(Index);
		// sanity check
		if (NumTracks <= 0) {
			FFMS_DestroyIndex(Index);
			Index = NULL;
			throw _T("FFmpegSource audio provider: no tracks found in index file");
		}

		for (int i = 0; i < NumTracks; i++) {
			FFTrack *TrackData = FFMS_GetTrackFromIndex(Index, i);
			// more sanity checking
			if (TrackData == NULL) {
				FFMS_DestroyIndex(Index);
				Index = NULL;
				wxString temp(FFMSErrMsg, wxConvUTF8);
				MsgString << _T("Couldn't get track data: ") << temp;
				throw MsgString;
			}

			// does the track have any indexed frames?
			if (FFMS_GetNumFrames(TrackData) <= 0 && (FFMS_GetTrackType(TrackData) == FFMS_TYPE_AUDIO)) {
				// found an unindexed audio track, we'll need to reindex
				FFMS_DestroyIndex(Index);
				Index = NULL;
				ReIndex = true;
				break;
			}
		}
	}
	
	// index didn't exist or was invalid, we'll have to (re)create it
	if (ReIndex) {
		try {
			Index = DoIndexing(Index, FileNameWX, CacheName, FFMSTrackMaskAll, false);
		} catch (wxString temp) {
			MsgString << temp;
			throw MsgString;
		} catch (...) {
			throw;
		}
	}

	// update access time of index file so it won't get cleaned away
	wxFileName(CacheName).Touch();

	// FIXME: provide a way to choose which audio track to load?
	int TrackNumber = FFMS_GetFirstTrackOfType(Index, FFMS_TYPE_AUDIO, FFMSErrMsg, MsgSize);
	if (TrackNumber < 0) {
		FFMS_DestroyIndex(Index);
		Index = NULL;
		wxString temp(FFMSErrMsg, wxConvUTF8);
		MsgString << _T("Couldn't find any audio tracks: ") << temp;
		throw MsgString;
	}

	AudioSource = FFMS_CreateAudioSource(FileNameWX.mb_str(wxConvUTF8), TrackNumber, Index, FFMSErrMsg, MsgSize);
	FFMS_DestroyIndex(Index);
	Index = NULL;
	if (!AudioSource) {
			wxString temp(FFMSErrMsg, wxConvUTF8);
			MsgString << _T("Failed to open audio track: ") << temp;
			throw MsgString;
	}
		
	const FFAudioProperties AudioInfo = *FFMS_GetAudioProperties(AudioSource);

	channels	= AudioInfo.Channels;
	sample_rate	= AudioInfo.SampleRate;
	num_samples = AudioInfo.NumSamples;
	if (channels <= 0 || sample_rate <= 0 || num_samples <= 0)
		throw _T("FFmpegSource audio provider: sanity check failed, consult your local psychiatrist");

	// FIXME: use 
	// why not just bits_per_sample/8? maybe there's some oddball format with half bytes out there somewhere...
	switch (AudioInfo.BitsPerSample) {
		case 8:		bytes_per_sample = 1; break;
		case 16:	bytes_per_sample = 2; break;
		case 24:	bytes_per_sample = 3; break;
		case 32:	bytes_per_sample = 4; break;
		default:
			throw _T("FFmpegSource audio provider: unknown or unsupported sample format");
	}
}


///////////
// Destructor
FFmpegSourceAudioProvider::~FFmpegSourceAudioProvider() {
	Close();
#ifdef WIN32
	if (COMInited)
		CoUninitialize();
#endif
}


///////////
// Clean up
void FFmpegSourceAudioProvider::Close() {
	FFMS_DestroyAudioSource(AudioSource);
	AudioSource = NULL;
}


///////////
// Get audio
void FFmpegSourceAudioProvider::GetAudio(void *Buf, int64_t Start, int64_t Count) {
	if (FFMS_GetAudio(AudioSource, Buf, Start, Count, FFMSErrMsg, MsgSize)) {
		wxString temp(FFMSErrMsg, wxConvUTF8);
		MsgString << _T("Failed to get audio samples: ") << temp;
		throw MsgString;
	}
}


#endif /* WITH_FFMPEGSOURCE */