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diff --git a/ext/mplex/mpastrm_in.cc b/ext/mplex/mpastrm_in.cc
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+/*
+ * audiostrm_in.c: MPEG Audio strem class members handling scanning
+ * and buffering raw input stream.
+ *
+ * Copyright (C) 2001 Andrew Stevens <andrew.stevens@philips.com>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public License
+ * as published by the Free Software Foundation.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <config.h>
+#include <math.h>
+#include <stdlib.h>
+
+#include "audiostrm.hh"
+#include "outputstream.hh"
+
+
+static const char *mpa_audio_version[4] = {
+ "2.5",
+ "2.0",
+ "reserved",
+ "1.0"
+};
+
+static const unsigned int mpa_bitrates_kbps[4][3][16] = {
+ { /* MPEG audio V2.5 */
+ {0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256, 0},
+ {0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0},
+ {0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0}
+ },
+ { /*RESERVED*/ {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+ {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+ {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+ },
+ { /* MPEG audio V2 */
+ {0, 32, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224, 256, 0},
+ {0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0},
+ {0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0}
+ },
+ { /* MPEG audio V1 */
+ {0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448, 0},
+ {0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384, 0},
+ {0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 0}
+ }
+
+};
+
+
+static const int mpa_freq_table[4][4] = {
+ /* MPEG audio V2.5 */
+ {11025, 12000, 8000, 0},
+ /* RESERVED */
+ {0, 0, 0, 0},
+ /* MPEG audio V2 */
+ {22050, 24000, 16000, 0},
+ /* MPEG audio V1 */
+ {44100, 48000, 32000, 0}
+};
+
+static const char mpa_stereo_mode[4][15] =
+ { "stereo", "joint stereo", "dual channel", "single channel" };
+static const char mpa_copyright_status[2][20] = { "no copyright", "copyright protected" };
+static const char mpa_original_bit[2][10] = { "copy", "original" };
+static const char mpa_emphasis_mode[4][20] =
+ { "none", "50/15 microseconds", "reserved", "CCITT J.17" };
+static const unsigned int mpa_slots[4] = { 12, 144, 144, 0 };
+static const unsigned int mpa_samples[4] = { 384, 1152, 1152, 0 };
+
+
+
+MPAStream::MPAStream (IBitStream & ibs, OutputStream & into):
+AudioStream (ibs, into)
+{
+}
+
+bool
+MPAStream::Probe (IBitStream & bs)
+{
+ return bs.getbits (11) == AUDIO_SYNCWORD;
+}
+
+
+/*************************************************************************
+ *
+ * Reads initial stream parameters and displays feedback banner to users
+ *
+ *************************************************************************/
+
+
+void
+MPAStream::Init (const int stream_num)
+{
+ int padding_bit;
+
+ MuxStream::Init (AUDIO_STR_0 + stream_num, 0, // Buffer scale
+ muxinto.audio_buffer_size,
+ muxinto.vcd_zero_stuffing,
+ muxinto.buffers_in_audio, muxinto.always_buffers_in_audio);
+ mjpeg_info ("Scanning for header info: Audio stream %02x", AUDIO_STR_0 + stream_num);
+
+ InitAUbuffer ();
+
+ /* A.Stevens 2000 - update to be compatible up to MPEG2.5
+ */
+ AU_start = bs.bitcount ();
+ if (bs.getbits (11) == AUDIO_SYNCWORD) {
+ num_syncword++;
+ version_id = bs.getbits (2);
+ layer = 3 - bs.getbits (2); /* 0..2 not 1..3!! */
+ protection = bs.get1bit ();
+ bit_rate_code = bs.getbits (4);
+ frequency = bs.getbits (2);
+ padding_bit = bs.get1bit ();
+ bs.get1bit ();
+ mode = bs.getbits (2);
+ mode_extension = bs.getbits (2);
+ copyright = bs.get1bit ();
+ original_copy = bs.get1bit ();
+ emphasis = bs.getbits (2);
+
+ framesize =
+ mpa_bitrates_kbps[version_id][layer][bit_rate_code] *
+ mpa_slots[layer] * 1000 / mpa_freq_table[version_id][frequency];
+
+ size_frames[0] = framesize;
+ size_frames[1] = framesize + (layer == 0 ? 4 : 1);
+ num_frames[padding_bit]++;
+ access_unit.start = AU_start;
+ access_unit.length = size_frames[padding_bit];
+
+ samples_per_second = mpa_freq_table[version_id][frequency];
+
+ /* Presentation time-stamping */
+ access_unit.PTS = static_cast < clockticks > (decoding_order) *
+ static_cast < clockticks > (mpa_samples[layer]) *
+ static_cast < clockticks > (CLOCKS) / samples_per_second;
+ access_unit.DTS = access_unit.PTS;
+ access_unit.dorder = decoding_order;
+ ++decoding_order;
+ aunits.append (access_unit);
+
+ } else {
+ mjpeg_error ("Invalid MPEG Audio stream header.");
+ exit (1);
+ }
+
+
+ OutputHdrInfo ();
+}
+
+unsigned int
+MPAStream::NominalBitRate ()
+{
+ return mpa_bitrates_kbps[version_id][layer][bit_rate_code] * 128;
+}
+
+
+unsigned int
+MPAStream::SizeFrame (int rate_code, int padding)
+{
+ return mpa_bitrates_kbps[version_id][layer][rate_code] *
+ mpa_slots[layer] * 1000 / mpa_freq_table[version_id][frequency] + padding;
+}
+
+void
+MPAStream::FillAUbuffer (unsigned int frames_to_buffer)
+{
+ unsigned int i;
+ unsigned int padding_bit;
+
+ last_buffered_AU += frames_to_buffer;
+
+ mjpeg_debug ("Scanning %d MPEG audio frames to frame %d", frames_to_buffer, last_buffered_AU);
+
+ while (!bs.eos () &&
+ decoding_order < last_buffered_AU) {
+
+ skip = access_unit.length - 4;
+ if (skip & 0x1)
+ bs.getbits (8);
+ if (skip & 0x2)
+ bs.getbits (16);
+ skip = skip >> 2;
+
+ for (i = 0; i < skip; i++) {
+ bs.getbits (32);
+ }
+ prev_offset = AU_start;
+ AU_start = bs.bitcount ();
+
+ /* Check we have reached the end of have another catenated
+ stream to process before finishing ... */
+ if ((syncword = bs.getbits (11)) != AUDIO_SYNCWORD) {
+ if (!bs.eobs) {
+ /* There appears to be another catenated stream... */
+ int next;
+
+ mjpeg_warn ("End of component bit-stream ... seeking next");
+ /* Catenated stream must start on byte boundary */
+ syncword = (syncword << (8 - AU_start % 8));
+ next = bs.getbits (8 - (AU_start % 8));
+ AU_start = bs.bitcount () - 11;
+ syncword = syncword | next;
+ if (syncword != AUDIO_SYNCWORD) {
+ mjpeg_warn ("Failed to find start of next stream at %lld prev %lld !", AU_start / 8,
+ prev_offset / 8);
+ break;
+ }
+ } else
+ /* No catenated stream... finished! */
+ break;
+ }
+ // Skip version_id:2, layer:2, protection:1
+ (void) bs.getbits (5);
+ int rate_code = bs.getbits (4);
+
+ // Skip frequency
+ (void) bs.getbits (2);
+
+ padding_bit = bs.get1bit ();
+ access_unit.start = AU_start;
+ access_unit.length = SizeFrame (rate_code, padding_bit);
+ access_unit.PTS =
+ static_cast < clockticks > (decoding_order) * static_cast < clockticks >
+ (mpa_samples[layer]) * static_cast < clockticks > (CLOCKS)
+ / samples_per_second;
+ access_unit.DTS = access_unit.PTS;
+ access_unit.dorder = decoding_order;
+ decoding_order++;
+ aunits.append (access_unit);
+ num_frames[padding_bit]++;
+
+ bs.getbits (9);
+
+ num_syncword++;
+
+ if (num_syncword >= old_frames + 10) {
+ mjpeg_debug ("Got %d frame headers.", num_syncword);
+ old_frames = num_syncword;
+
+ }
+
+
+
+ }
+ last_buffered_AU = decoding_order;
+ eoscan = bs.eos ();
+
+}
+
+
+
+void
+MPAStream::Close ()
+{
+ stream_length = AU_start >> 3;
+ mjpeg_info ("AUDIO_STATISTICS: %02x", stream_id);
+ mjpeg_info ("Audio stream length %lld bytes.", stream_length);
+ mjpeg_info ("Syncwords : %8u", num_syncword);
+ mjpeg_info ("Frames : %8u padded", num_frames[0]);
+ mjpeg_info ("Frames : %8u unpadded", num_frames[1]);
+
+ bs.close ();
+}
+
+/*************************************************************************
+ OutputAudioInfo
+ gibt gesammelte Informationen zu den Audio Access Units aus.
+
+ Prints information on audio access units
+*************************************************************************/
+
+void
+MPAStream::OutputHdrInfo ()
+{
+ unsigned int bitrate;
+
+ bitrate = mpa_bitrates_kbps[version_id][layer][bit_rate_code];
+
+
+ mjpeg_info ("AUDIO STREAM:");
+ mjpeg_info ("Audio version : %s", mpa_audio_version[version_id]);
+ mjpeg_info ("Layer : %8u", layer + 1);
+
+ if (protection == 0)
+ mjpeg_info ("CRC checksums : yes");
+ else
+ mjpeg_info ("CRC checksums : no");
+
+ if (bit_rate_code == 0)
+ mjpeg_info ("Bit rate : free");
+ else if (bit_rate_code == 0xf)
+ mjpeg_info ("Bit rate : reserved");
+ else
+ mjpeg_info ("Bit rate : %8u bytes/sec (%3u kbit/sec)", bitrate * 128, bitrate);
+
+ if (frequency == 3)
+ mjpeg_info ("Frequency : reserved");
+ else
+ mjpeg_info ("Frequency : %d Hz", mpa_freq_table[version_id][frequency]);
+
+ mjpeg_info ("Mode : %8u %s", mode, mpa_stereo_mode[mode]);
+ mjpeg_info ("Mode extension : %8u", mode_extension);
+ mjpeg_info ("Copyright bit : %8u %s", copyright, mpa_copyright_status[copyright]);
+ mjpeg_info ("Original/Copy : %8u %s", original_copy, mpa_original_bit[original_copy]);
+ mjpeg_info ("Emphasis : %8u %s", emphasis, mpa_emphasis_mode[emphasis]);
+}
+
+
+
+/*
+ * Local variables:
+ * c-file-style: "stroustrup"
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
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