///////////////////////////// executable code ////////////////////////////////
// Read the median log2 values from the specifed metadata structure, convert
// them back to 32-bit unsigned values and store them. If length is not
// exactly correct then we flag and return an error.
internal static int read_entropy_vars(WavpackStream wps, WavpackMetadata wpmd)
{
byte[] byteptr = wpmd.data;
int[] b_array = new int[12];
int i = 0;
words_data w = new words_data();
for (i = 0; i < 6; i++)
{
b_array[i] = (int)(byteptr[i] & 0xff);
}
w.holding_one = 0;
w.holding_zero = 0;
if (wpmd.byte_length != 12)
{
if ((wps.wphdr.flags & (Defines.MONO_FLAG | Defines.FALSE_STEREO)) == 0)
{
return(Defines.FALSE);
}
}
w.c[0].median[0] = exp2s(b_array[0] + (b_array[1] << 8));
w.c[0].median[1] = exp2s(b_array[2] + (b_array[3] << 8));
w.c[0].median[2] = exp2s(b_array[4] + (b_array[5] << 8));
if ((wps.wphdr.flags & (Defines.MONO_FLAG | Defines.FALSE_STEREO)) == 0)
{
for (i = 6; i < 12; i++)
{
b_array[i] = (int)(byteptr[i] & 0xff);
}
w.c[1].median[0] = exp2s(b_array[6] + (b_array[7] << 8));
w.c[1].median[1] = exp2s(b_array[8] + (b_array[9] << 8));
w.c[1].median[2] = exp2s(b_array[10] + (b_array[11] << 8));
}
wps.w = w;
return(Defines.TRUE);
}
internal static int[] float_values(WavpackStream wps, int[] values, long num_values, int bufferStartPos)
{
int shift = wps.float_max_exp - wps.float_norm_exp + wps.float_shift;
int value_counter = bufferStartPos;
if (shift > 32)
{
shift = 32;
}
else if (shift < -32)
{
shift = -32;
}
while (num_values > 0)
{
if (shift > 0)
{
values[value_counter] <<= shift;
}
else if (shift < 0)
{
values[value_counter] >>= -shift;
}
if (values[value_counter] > 8388607L)
{
values[value_counter] = (int)SupportClass.Identity(8388607L);
}
else if (values[value_counter] < -8388608L)
{
values[value_counter] = (int)SupportClass.Identity(-8388608L);
}
value_counter++;
num_values--;
}
return(values);
}
internal static int read_float_info(WavpackStream wps, WavpackMetadata wpmd)
{
int bytecnt = wpmd.byte_length;
byte[] byteptr = wpmd.data;
int counter = 0;
if (bytecnt != 4)
{
return(Defines.FALSE);
}
wps.float_flags = byteptr[counter];
counter++;
wps.float_shift = byteptr[counter];
counter++;
wps.float_max_exp = byteptr[counter];
counter++;
wps.float_norm_exp = byteptr[counter];
return(Defines.TRUE);
}
// Find the WavPack block that contains the specified sample. If "header_pos"
// is zero, then no information is assumed except the total number of samples
// in the file and its size in bytes. If "header_pos" is non-zero then we
// assume that it is the file position of the valid header image contained in
// the first stream and we can limit our search to either the portion above
// or below that point. If a .wvc file is being used, then this must be called
// for that file also.
private static void seek(WavpackContext wpc, System.IO.BinaryReader infile, long headerPos, long targetSample)
{
try
{
WavpackStream wps = wpc.stream;
long file_pos1 = 0;
long file_pos2 = wpc.infile.BaseStream.Length;
long sample_pos1 = 0, sample_pos2 = wpc.total_samples;
double ratio = 0.96;
int file_skip = 0;
if (targetSample >= wpc.total_samples)
{
return;
}
if (headerPos > 0 && wps.wphdr.block_samples > 0)
{
if (wps.wphdr.block_index > targetSample)
{
sample_pos2 = wps.wphdr.block_index;
file_pos2 = headerPos;
}
else if (wps.wphdr.block_index + wps.wphdr.block_samples <= targetSample)
{
sample_pos1 = wps.wphdr.block_index;
file_pos1 = headerPos;
}
else
{
return;
}
}
while (true)
{
double bytes_per_sample;
long seek_pos;
bytes_per_sample = file_pos2 - file_pos1;
bytes_per_sample /= sample_pos2 - sample_pos1;
seek_pos = file_pos1 + (file_skip > 0 ? 32 : 0);
seek_pos += (long)(bytes_per_sample * (targetSample - sample_pos1) * ratio);
infile.BaseStream.Seek(seek_pos, 0);
long temppos = infile.BaseStream.Position;
wps.wphdr = read_next_header(infile, wps.wphdr);
if (wps.wphdr.status == 1 || seek_pos >= file_pos2)
{
if (ratio > 0.0)
{
if ((ratio -= 0.24) < 0.0)
{
ratio = 0.0;
}
}
else
{
return;
}
}
else if (wps.wphdr.block_index > targetSample)
{
sample_pos2 = wps.wphdr.block_index;
file_pos2 = seek_pos;
}
else if (wps.wphdr.block_index + wps.wphdr.block_samples <= targetSample)
{
if (seek_pos == file_pos1)
{
file_skip = 1;
}
else
{
sample_pos1 = wps.wphdr.block_index;
file_pos1 = seek_pos;
}
}
else
{
int index = (int)(targetSample - wps.wphdr.block_index);
infile.BaseStream.Seek(seek_pos, 0);
WavpackContext c = WavpackOpenFileInput(infile);
wpc.stream = c.stream;
int[] temp_buf = new int[Defines.SAMPLE_BUFFER_SIZE];
while (index > 0)
{
int toUnpack = Math.Min(index, Defines.SAMPLE_BUFFER_SIZE / WavpackGetReducedChannels(wpc));
WavpackUnpackSamples(wpc, temp_buf, toUnpack);
index = index - toUnpack;
}
return;
}
}
}
catch (System.IO.IOException)
{
}
}
///////////////////////////// executable code ////////////////////////////////
// This function reads data from the specified stream in search of a valid
// WavPack 4.0 audio block. If this fails in 1 megabyte (or an invalid or
// unsupported WavPack block is encountered) then an appropriate message is
// copied to "error" and NULL is returned, otherwise a pointer to a
// WavpackContext structure is returned (which is used to call all other
// functions in this module). This can be initiated at the beginning of a
// WavPack file, or anywhere inside a WavPack file. To determine the exact
// position within the file use WavpackGetSampleIndex(). Also,
// this function will not handle "correction" files, plays only the first
// two channels of multi-channel files, and is limited in resolution in some
// large integer or floating point files (but always provides at least 24 bits
// of resolution).
public static WavpackContext WavpackOpenFileInput(System.IO.BinaryReader infile)
{
WavpackContext wpc = new WavpackContext();
WavpackStream wps = wpc.stream;
wpc.infile = infile;
wpc.total_samples = -1;
wpc.norm_offset = 0;
wpc.open_flags = 0;
// open the source file for reading and store the size
while (wps.wphdr.block_samples == 0)
{
wps.wphdr = read_next_header(wpc.infile, wps.wphdr);
if (wps.wphdr.status == 1)
{
wpc.error_message = "not compatible with this version of WavPack file!";
wpc.error = true;
return(wpc);
}
if (wps.wphdr.block_samples > 0 && wps.wphdr.total_samples != -1)
{
wpc.total_samples = wps.wphdr.total_samples;
}
// lets put the stream back in the context
wpc.stream = wps;
if ((UnpackUtils.unpack_init(wpc)) == Defines.FALSE)
{
wpc.error = true;
return(wpc);
}
} // end of while
wpc.config.flags = wpc.config.flags & ~0xff;
wpc.config.flags = wpc.config.flags | (wps.wphdr.flags & 0xff);
wpc.config.bytes_per_sample = (int)((wps.wphdr.flags & Defines.BYTES_STORED) + 1);
wpc.config.float_norm_exp = wps.float_norm_exp;
wpc.config.bits_per_sample = (int)((wpc.config.bytes_per_sample * 8) - ((wps.wphdr.flags & Defines.SHIFT_MASK) >> Defines.SHIFT_LSB));
if ((wpc.config.flags & Defines.FLOAT_DATA) > 0)
{
wpc.config.bytes_per_sample = 3;
wpc.config.bits_per_sample = 24;
}
if (wpc.config.sample_rate == 0)
{
if (wps.wphdr.block_samples == 0 || (wps.wphdr.flags & Defines.SRATE_MASK) == Defines.SRATE_MASK)
{
wpc.config.sample_rate = 44100;
}
else
{
wpc.config.sample_rate = sample_rates[(int)((wps.wphdr.flags & Defines.SRATE_MASK) >> Defines.SRATE_LSB)];
}
}
if (wpc.config.num_channels == 0)
{
if ((wps.wphdr.flags & Defines.MONO_FLAG) > 0)
{
wpc.config.num_channels = 1;
}
else
{
wpc.config.num_channels = 2;
}
wpc.config.channel_mask = 0x5 - wpc.config.num_channels;
}
if ((wps.wphdr.flags & Defines.FINAL_BLOCK) == 0)
{
if ((wps.wphdr.flags & Defines.MONO_FLAG) != 0)
{
wpc.reduced_channels = 1;
}
else
{
wpc.reduced_channels = 2;
}
}
return(wpc);
}
// Unpack the specified number of samples from the current file position.
// Note that "samples" here refers to "complete" samples, which would be
// 2 longs for stereo files. The audio data is returned right-justified in
// 32-bit longs in the endian mode native to the executing processor. So,
// if the original data was 16-bit, then the values returned would be
// +/-32k. Floating point data will be returned as 24-bit integers (and may
// also be clipped). The actual number of samples unpacked is returned,
// which should be equal to the number requested unless the end of fle is
// encountered or an error occurs.
internal static long WavpackUnpackSamples(WavpackContext wpc, int[] buffer, long samples)
{
WavpackStream wps = wpc.stream;
long samples_unpacked = 0, samples_to_unpack;
int num_channels = wpc.config.num_channels;
int bcounter = 0;
int buf_idx = 0;
int bytes_returned = 0;
while (samples > 0)
{
if (wps.wphdr.block_samples == 0 || (wps.wphdr.flags & Defines.INITIAL_BLOCK) == 0 || wps.sample_index >= wps.wphdr.block_index + wps.wphdr.block_samples)
{
wps.wphdr = read_next_header(wpc.infile, wps.wphdr);
if (wps.wphdr.status == 1)
{
break;
}
if (wps.wphdr.block_samples == 0 || wps.sample_index == wps.wphdr.block_index)
{
if ((UnpackUtils.unpack_init(wpc)) == Defines.FALSE)
{
break;
}
}
}
if (wps.wphdr.block_samples == 0 || (wps.wphdr.flags & Defines.INITIAL_BLOCK) == 0 || wps.sample_index >= wps.wphdr.block_index + wps.wphdr.block_samples)
{
continue;
}
if (wps.sample_index < wps.wphdr.block_index)
{
samples_to_unpack = wps.wphdr.block_index - wps.sample_index;
if (samples_to_unpack > samples)
{
samples_to_unpack = samples;
}
wps.sample_index += samples_to_unpack;
samples_unpacked += samples_to_unpack;
samples -= samples_to_unpack;
if (wpc.reduced_channels > 0)
{
samples_to_unpack *= wpc.reduced_channels;
}
else
{
samples_to_unpack *= num_channels;
}
bcounter = buf_idx;
while (samples_to_unpack > 0)
{
buffer[bcounter] = 0;
bcounter++;
samples_to_unpack--;
}
buf_idx = bcounter;
continue;
}
samples_to_unpack = wps.wphdr.block_index + wps.wphdr.block_samples - wps.sample_index;
if (samples_to_unpack > samples)
{
samples_to_unpack = samples;
}
UnpackUtils.unpack_samples(wpc, buffer, samples_to_unpack, buf_idx);
if (wpc.reduced_channels > 0)
{
bytes_returned = (int)(samples_to_unpack * wpc.reduced_channels);
}
else
{
bytes_returned = (int)(samples_to_unpack * num_channels);
}
buf_idx += bytes_returned;
samples_unpacked += samples_to_unpack;
samples -= samples_to_unpack;
if (wps.sample_index == wps.wphdr.block_index + wps.wphdr.block_samples)
{
if (UnpackUtils.check_crc_error(wpc) > 0)
{
wpc.crc_errors++;
}
}
if (wps.sample_index == wpc.total_samples)
{
break;
}
}
return(samples_unpacked);
}
// Read the hybrid related values from the specifed metadata structure, convert
// them back to their internal formats and store them. The extended profile
// stuff is not implemented yet, so return an error if we get more data than
// we know what to do with.
internal static int read_hybrid_profile(WavpackStream wps, WavpackMetadata wpmd)
{
byte[] byteptr = wpmd.data;
int bytecnt = wpmd.byte_length;
int buffer_counter = 0;
int uns_buf = 0;
int uns_buf_plusone = 0;
if ((wps.wphdr.flags & Defines.HYBRID_BITRATE) != 0)
{
uns_buf = (int)(byteptr[buffer_counter] & 0xff);
uns_buf_plusone = (int)(byteptr[buffer_counter + 1] & 0xff);
wps.w.c[0].slow_level = exp2s(uns_buf + (uns_buf_plusone << 8));
buffer_counter = buffer_counter + 2;
if ((wps.wphdr.flags & (Defines.MONO_FLAG | Defines.FALSE_STEREO)) == 0)
{
uns_buf = (int)(byteptr[buffer_counter] & 0xff);
uns_buf_plusone = (int)(byteptr[buffer_counter + 1] & 0xff);
wps.w.c[1].slow_level = exp2s(uns_buf + (uns_buf_plusone << 8));
buffer_counter = buffer_counter + 2;
}
}
uns_buf = (int)(byteptr[buffer_counter] & 0xff);
uns_buf_plusone = (int)(byteptr[buffer_counter + 1] & 0xff);
wps.w.bitrate_acc[0] = (int)(uns_buf + (uns_buf_plusone << 8)) << 16;
buffer_counter = buffer_counter + 2;
if ((wps.wphdr.flags & (Defines.MONO_FLAG | Defines.FALSE_STEREO)) == 0)
{
uns_buf = (int)(byteptr[buffer_counter] & 0xff);
uns_buf_plusone = (int)(byteptr[buffer_counter + 1] & 0xff);
wps.w.bitrate_acc[1] = (int)(uns_buf + (uns_buf_plusone << 8)) << 16;
buffer_counter = buffer_counter + 2;
}
if (buffer_counter < bytecnt)
{
uns_buf = (int)(byteptr[buffer_counter] & 0xff);
uns_buf_plusone = (int)(byteptr[buffer_counter + 1] & 0xff);
wps.w.bitrate_delta[0] = exp2s((short)(uns_buf + (uns_buf_plusone << 8)));
buffer_counter = buffer_counter + 2;
if ((wps.wphdr.flags & (Defines.MONO_FLAG | Defines.FALSE_STEREO)) == 0)
{
uns_buf = (int)(byteptr[buffer_counter] & 0xff);
uns_buf_plusone = (int)(byteptr[buffer_counter + 1] & 0xff);
wps.w.bitrate_delta[1] = exp2s((short)(uns_buf + (uns_buf_plusone << 8)));
buffer_counter = buffer_counter + 2;
}
if (buffer_counter < bytecnt)
{
return(Defines.FALSE);
}
}
else
{
wps.w.bitrate_delta[0] = wps.w.bitrate_delta[1] = 0;
}
return(Defines.TRUE);
}
internal static int process_metadata(WavpackContext wpc, WavpackMetadata wpmd)
{
WavpackStream wps = wpc.stream;
switch (wpmd.id)
{
case Defines.ID_DUMMY:
{
return(Defines.TRUE);
}
case Defines.ID_DECORR_TERMS:
{
return(UnpackUtils.read_decorr_terms(wps, wpmd));
}
case Defines.ID_DECORR_WEIGHTS:
{
return(UnpackUtils.read_decorr_weights(wps, wpmd));
}
case Defines.ID_DECORR_SAMPLES:
{
return(UnpackUtils.read_decorr_samples(wps, wpmd));
}
case Defines.ID_ENTROPY_VARS:
{
return(WordsUtils.read_entropy_vars(wps, wpmd));
}
case Defines.ID_HYBRID_PROFILE:
{
return(WordsUtils.read_hybrid_profile(wps, wpmd));
}
case Defines.ID_FLOAT_INFO:
{
return(FloatUtils.read_float_info(wps, wpmd));
}
case Defines.ID_INT32_INFO:
{
return(UnpackUtils.read_int32_info(wps, wpmd));
}
case Defines.ID_CHANNEL_INFO:
{
return(UnpackUtils.read_channel_info(wpc, wpmd));
}
case Defines.ID_SAMPLE_RATE:
{
return(UnpackUtils.read_sample_rate(wpc, wpmd));
}
case Defines.ID_CONFIG_BLOCK:
{
return(UnpackUtils.read_config_info(wpc, wpmd));
}
case Defines.ID_WV_BITSTREAM:
{
return(UnpackUtils.init_wv_bitstream(wpc, wpmd));
}
case Defines.ID_SHAPING_WEIGHTS:
case Defines.ID_WVC_BITSTREAM:
case Defines.ID_WVX_BITSTREAM:
{
return(Defines.TRUE);
}
default:
{
if ((wpmd.id & Defines.ID_OPTIONAL_DATA) != 0)
{
return(Defines.TRUE);
}
else
{
return(Defines.FALSE);
}
}
break;
}
}
