コード例 #1
0
        public unsafe void writeints(int len, int pos, byte *buf)
        {
            int old_pos = BitLength;
            int start   = old_pos / 8;
            int start1  = pos / 8;
            int end     = (old_pos + len) / 8;
            int end1    = (pos + len) / 8;

            flush();
            byte start_val = old_pos % 8 != 0 ? buffer[start] : (byte)0;

            fixed(byte *buf1 = &buffer[0])
            {
                if (old_pos % 8 != 0)
                {
                    crc16_m = Crc16.Substract(crc16_m, 0, 1);
                }
                crc16_m = Crc16.ComputeChecksum(crc16_m, buf + start1, end - start);
                AudioSamples.MemCpy(buf1 + start, buf + start1, end - start);
                buf1[start] |= start_val;
            }

            buf_ptr_m = end;
            if ((old_pos + len) % 8 != 0)
            {
                writebits((old_pos + len) % 8, buf[end1] >> (8 - ((old_pos + len) % 8)));
            }
        }
コード例 #2
0
        unsafe void fill_frames_buffer()
        {
            if (_framesBufferLength == 0)
            {
                _framesBufferOffset = 0;
            }
            else if (_framesBufferLength < _framesBuffer.Length / 2 && _framesBufferOffset >= _framesBuffer.Length / 2)
            {
                fixed(byte *buff = _framesBuffer)
                AudioSamples.MemCpy(buff, buff + _framesBufferOffset, _framesBufferLength);

                _framesBufferOffset = 0;
            }
            long readCount = 0;

            while (_framesBufferLength < _framesBuffer.Length / 2)
            {
                readCount++;
                int read = _IO.Read(_framesBuffer, _framesBufferOffset + _framesBufferLength, _framesBuffer.Length - _framesBufferOffset - _framesBufferLength);
                _framesBufferLength += read;
                if (read == 0)
                {
                    break;
                }
            }
        }
コード例 #3
0
        unsafe void Restore_samples_fixed(FlacFrame frame, int ch)
        {
            FlacSubframeInfo sub = frame.subframes[ch];

            AudioSamples.MemCpy(sub.samples, sub.best.residual, sub.best.order);
            int *data = sub.samples + sub.best.order;
            int *residual = sub.best.residual + sub.best.order;
            int  data_len = frame.blocksize - sub.best.order;
            int  s0, s1, s2;

            switch (sub.best.order)
            {
            case 0:
                AudioSamples.MemCpy(data, residual, data_len);
                break;

            case 1:
                s1 = data[-1];
                for (int i = data_len; i > 0; i--)
                {
                    s1       += *(residual++);
                    *(data++) = s1;
                }
                //data[i] = residual[i] + data[i - 1];
                break;

            case 2:
                s2 = data[-2];
                s1 = data[-1];
                for (int i = data_len; i > 0; i--)
                {
                    s0        = *(residual++) + (s1 << 1) - s2;
                    *(data++) = s0;
                    s2        = s1;
                    s1        = s0;
                }
                //data[i] = residual[i] + data[i - 1] * 2  - data[i - 2];
                break;

            case 3:
                for (int i = 0; i < data_len; i++)
                {
                    data[i] = residual[i] + (((data[i - 1] - data[i - 2]) << 1) + (data[i - 1] - data[i - 2])) + data[i - 3];
                }
                break;

            case 4:
                for (int i = 0; i < data_len; i++)
                {
                    data[i] = residual[i] + ((data[i - 1] + data[i - 3]) << 2) - ((data[i - 2] << 2) + (data[i - 2] << 1)) - data[i - 4];
                }
                break;
            }
        }
コード例 #4
0
        unsafe void Restore_samples(FlacFrame frame)
        {
            for (int ch = 0; ch < PCM.ChannelCount; ch++)
            {
                switch (frame.subframes[ch].best.type)
                {
                case SubframeType.Constant:
                    AudioSamples.MemSet(frame.subframes[ch].samples, frame.subframes[ch].best.residual[0], frame.blocksize);
                    break;

                case SubframeType.Verbatim:
                    AudioSamples.MemCpy(frame.subframes[ch].samples, frame.subframes[ch].best.residual, frame.blocksize);
                    break;

                case SubframeType.Fixed:
                    Restore_samples_fixed(frame, ch);
                    break;

                case SubframeType.LPC:
                    Restore_samples_lpc(frame, ch);
                    break;
                }
                if (frame.subframes[ch].wbits != 0)
                {
                    int *s = frame.subframes[ch].samples;
                    int  x = (int)frame.subframes[ch].wbits;
                    for (int i = frame.blocksize; i > 0; i--)
                    {
                        *(s++) <<= x;
                    }
                }
            }
            if (frame.ch_mode != ChannelMode.NotStereo)
            {
                int *l = frame.subframes[0].samples;
                int *r = frame.subframes[1].samples;
                switch (frame.ch_mode)
                {
                case ChannelMode.LeftRight:
                    break;

                case ChannelMode.MidSide:
                    for (int i = frame.blocksize; i > 0; i--)
                    {
                        int mid  = *l;
                        int side = *r;
                        mid  <<= 1;
                        mid   |= (side & 1);                               /* i.e. if 'side' is odd... */
                        *(l++) = (mid + side) >> 1;
                        *(r++) = (mid - side) >> 1;
                    }
                    break;

                case ChannelMode.LeftSide:
                    for (int i = frame.blocksize; i > 0; i--)
                    {
                        int _l = *(l++), _r = *r;
                        *(r++) = _l - _r;
                    }
                    break;

                case ChannelMode.RightSide:
                    for (int i = frame.blocksize; i > 0; i--)
                    {
                        *(l++) += *(r++);
                    }
                    break;
                }
            }
        }