bool readReference(IBitStream& bstr, unsigned& reference, unsigned huffmanNumber) {
int code = bstr.read(2);
if (code == 3) {
reference = bstr.read(32);
return true;
}
int bitlen = BitLength(huffmanNumber);
assert(bitlen >= 2);
reference = (code << (bitlen - 2)) | bstr.read(bitlen - 2);
return true;
}
bool LPCMStream::Probe(IBitStream &bs )
{
char *last_dot = strrchr( bs.StreamName(), '.' );
return
last_dot != NULL
&& strcmp( last_dot+1, "lpcm") == 0;
}
std::u16string DictionaryReader::decodeArticle(IBitStream &bstr, unsigned reference) {
loadDecoder();
bstr.seek(header().articlesOffset + reference);
std::u16string body;
bool res = decoder()->DecodeArticle(&bstr, body);
if (!res)
throw std::runtime_error("can't decode article");
return body;
}
void LenTable::Read(IBitStream &bitstr) {
symidx2nodeidx.clear();
nodes.clear();
int count = bitstr.read(32);
int bitsPerLen = bitstr.read(8);
int idxBitSize = BitLength(count);
symidx2nodeidx.resize(count);
for (unsigned& nodeIdx : symidx2nodeidx) {
nodeIdx = -1; // in case the root has a leaf as a child
}
nodes.resize(count - 1);
int rootIdx = nodes.size() - 1;
nodes.at(rootIdx) = {0,0,-1,-1};
nextNodePosition = 0;
for (int i = 0; i < count; ++i) {
int symidx = bitstr.read(idxBitSize);
int len = bitstr.read(bitsPerLen);
placeSymidx(symidx, rootIdx, len);
}
}
std::vector<ArticleHeading> collectHeadingFromPage(IBitStream& bstr, DictionaryReader& reader, unsigned pageNumber) {
std::vector<ArticleHeading> res;
bstr.seek(reader.header().pagesOffset + 512 * pageNumber);
CachePage page;
page.loadHeader(bstr);
if (page.isLeaf()) {
std::u16string prefix;
for (size_t idx = 0; idx < page.headingsCount(); ++idx) {
ArticleHeading h;
h.Load(*reader.decoder(), bstr, prefix);
res.push_back(h);
}
}
return res;
}
int LenTable::Decode(IBitStream &bitstr, unsigned &symIdx) const {
const HuffmanNode* node = &nodes.back();
int len = 0;
for (;;) {
len++;
int bit = bitstr.read(1);
if (bit) { // right
if (node->right < 0) { // leaf
symIdx = -1 - node->right;
return len;
}
node = &nodes.at(node->right - 1);
} else { // left
if (node->left < 0) { // leaf
symIdx = -1 - node->left;
return len;
}
node = &nodes.at(node->left - 1);
}
}
// unreachable
}
bool DTSStream::Probe(IBitStream &bs )
{
return bs.GetBits(32) == DTS_SYNCWORD;
}
void MultiplexJob::SetupInputStreams( std::vector< IBitStream *> &inputs )
{
IBitStream *bs;
IBitStreamUndo undo;
unsigned int i;
bool bad_file = false;
for( i = 0; i < inputs.size(); ++i )
{
bs = inputs[i];
// Remember the streams initial state...
bs->PrepareUndo( undo );
if( LPCMStream::Probe( *bs ) )
{
mjpeg_info ("File %s looks like an LPCM Audio stream.",
bs->StreamName());
bs->UndoChanges( undo );
streams.push_back( new JobStream( bs, LPCM_AUDIO) );
++audio_tracks;
++lpcm_tracks;
continue;
}
bs->UndoChanges( undo );
if( MPAStream::Probe( *bs ) )
{
mjpeg_info ("File %s looks like an MPEG Audio stream.",
bs->StreamName() );
bs->UndoChanges( undo );
streams.push_back( new JobStream( bs, MPEG_AUDIO) );
++audio_tracks;
continue;
}
bs->UndoChanges( undo );
if( AC3Stream::Probe( *bs ) )
{
mjpeg_info ("File %s looks like an AC3 Audio stream.",
bs->StreamName());
bs->UndoChanges( undo );
streams.push_back( new JobStream( bs, AC3_AUDIO) );
++audio_tracks;
continue;
}
bs->UndoChanges( undo );
if( DTSStream::Probe( *bs ) )
{
mjpeg_info ("File %s looks like a dts Audio stream.",
bs->StreamName());
bs->UndoChanges( undo);
streams.push_back( new JobStream( bs, DTS_AUDIO) );
++audio_tracks;
continue;
}
bs->UndoChanges( undo );
if( VideoStream::Probe( *bs ) )
{
mjpeg_info ("File %s looks like an MPEG Video stream.",
bs->StreamName());
bs->UndoChanges( undo );
streams.push_back( new JobStream( bs, MPEG_VIDEO) );
++video_tracks;
continue;
}
bs->UndoChanges( undo );
if( SUBPStream::Probe( *bs ) )
{
mjpeg_info ("File %s looks like an Subpicture stream.",
bs->StreamName());
bs->UndoChanges( undo );
streams.push_back( new JobStream( bs, SUBP_STREAM) );
++subtitle_tracks;
continue;
}
#ifdef ZALPHA
if( ZAlphaStream::Probe( *bs ) )
{
mjpeg_info ("File %s looks like an Z/Alpha Video stream.",
bs->StreamName());
bs->UndoChanges( undo );
streams.push_back( new JobStream( bs, Z_ALPHA) );
++video_tracks;
++z_alpha_tracks;
continue;
}
#endif
bad_file = true;
mjpeg_error ("File %s unrecogniseable!", bs->StreamName());
delete bs;
}
if( bad_file )
{
mjpeg_error_exit1( "Unrecogniseable file(s)... exiting.");
}
//
// Where no parameters for streams have been specified
// simply set the default values (these will depend on the format
// we're muxing of course...)
//
for( i = video_param.size(); i < video_tracks; ++i )
{
video_param.push_back(VideoParams::Default( mux_format ));
}
for( i = lpcm_param.size(); i < lpcm_tracks; ++i )
{
lpcm_param.push_back(LpcmParams::Default(mux_format));
}
for( i = subtitle_params.size(); i < subtitle_tracks; ++i )
{
subtitle_params.push_back(SubtitleStreamParams::Default(mux_format));
}
//
// Set standard values if the selected profile implies this...
//
for( i = 0; i <video_tracks; ++i )
{
if( video_param[i]->Force(mux_format) )
{
mjpeg_info( "Video stream %d: profile %d selected - ignoring non-standard options!", i, mux_format );
}
}
mjpeg_info( "Found %d audio streams, %d video streams and %d subtitle streams",
audio_tracks,
video_tracks,
subtitle_tracks
);
}
bool MPAStream::Probe(IBitStream &bs )
{
return bs.GetBits(11) == AUDIO_SYNCWORD;
}
bool VideoStream::Probe(IBitStream &bs )
{
return bs.GetBits( 32) == 0x1b3;
}