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-rw-r--r--ext/mplex/ac3strm_in.cc383
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diff --git a/ext/mplex/ac3strm_in.cc b/ext/mplex/ac3strm_in.cc
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--- a/ext/mplex/ac3strm_in.cc
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@@ -1,383 +0,0 @@
-/*
- * ac3strm_in.c: AC3 Audio strem class members handling scanning and
- * buffering raw input stream.
- *
- * Copyright (C) 2001 Andrew Stevens <andrew.stevens@philips.com>
- * Copyright (C) 2000,2001 Brent Byeler for original header-structure
- * parsing code.
- *
- *
- * 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"
-#include <cassert>
-
-
-
-#define AC3_SYNCWORD 0x0b77
-#define AC3_PACKET_SAMPLES 1536
-
-/// table for the available AC3 bitrates
-static const unsigned int ac3_bitrate_index[32] =
-{
- 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192,
- 224, 256, 320, 384, 448, 512, 576, 640,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
-};
-
-static const unsigned int ac3_frame_size[3][32] =
-{
- {64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384,
- 448, 512, 640, 768, 896, 1024, 1152, 1280,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
- {69, 87, 104, 121, 139, 174, 208, 243, 278, 348, 417,
- 487, 557, 696, 835, 975, 1114, 1253, 1393,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
- {96, 120, 144, 168, 192, 240, 288, 336, 384, 480, 576,
- 672, 768, 960, 1152, 1344, 1536, 1728, 1920,
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
-};
-
-/// table for the available AC3 frequencies
-static const unsigned int ac3_frequency[4] = { 48000, 44100, 32000, 0 };
-
-
-AC3Stream::AC3Stream (IBitStream & ibs, OutputStream & into):
-AudioStream (ibs, into)
-{
-}
-
-bool
-AC3Stream::Probe (IBitStream & bs)
-{
- return bs.getbits (16) == AC3_SYNCWORD;
-}
-
-
-/*************************************************************************
- *
- * Reads initial stream parameters and displays feedback banner to users
- * @param stream_num AC3 substream ID
- *************************************************************************/
-
-
-void
-AC3Stream::Init (const int stream_num)
-{
- unsigned int framesize_code;
-
- this->stream_num = stream_num;
-
- MuxStream::Init (PRIVATE_STR_1, 1, // Buffer scale
- default_buffer_size,
- muxinto.vcd_zero_stuffing,
- muxinto.buffers_in_audio, muxinto.always_buffers_in_audio);
- mjpeg_info ("Scanning for header info: AC3 Audio stream %02x", stream_num);
-
- InitAUbuffer ();
- AU_start = bs.bitcount ();
- if (bs.getbits (16) == AC3_SYNCWORD) {
- num_syncword++;
- bs.getbits (16); // CRC field
- frequency = bs.getbits (2); // Sample rate code
- framesize_code = bs.getbits (6); // Frame size code
- framesize = ac3_frame_size[frequency][framesize_code >> 1];
- framesize = (framesize_code & 1) && frequency == 1 ? (framesize + 1) << 1 : (framesize << 1);
-
-
- size_frames[0] = framesize;
- size_frames[1] = framesize;
- num_frames[0]++;
- access_unit.start = AU_start;
- access_unit.length = framesize;
- bit_rate = ac3_bitrate_index[framesize_code >> 1];
- samples_per_second = ac3_frequency[frequency];
-
-
- /* Presentation time-stamping */
- access_unit.PTS = static_cast < clockticks > (decoding_order) *
- static_cast < clockticks > (AC3_PACKET_SAMPLES) *
- 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 AC3 Audio stream header.");
- exit (1);
- }
-
- OutputHdrInfo ();
-}
-
-/// @returns the current bitrate
-unsigned int
-AC3Stream::NominalBitRate ()
-{
- return bit_rate;
-}
-
-/// Prefills the internal buffer for output multiplexing.
-/// @param frames_to_buffer the number of audio frames to read ahead
-void
-AC3Stream::FillAUbuffer (unsigned int frames_to_buffer)
-{
- unsigned int framesize_code;
-
- last_buffered_AU += frames_to_buffer;
- mjpeg_debug ("Scanning %d MPEG audio frames to frame %d", frames_to_buffer, last_buffered_AU);
-
- static int header_skip = 5; // Initially skipped past 5 bytes of header
- int skip;
- bool bad_last_frame = false;
-
- while (!bs.eos () &&
- decoding_order < last_buffered_AU) {
- skip = access_unit.length - header_skip;
- if (skip & 0x1)
- bs.getbits (8);
- if (skip & 0x2)
- bs.getbits (16);
- skip = skip >> 2;
-
- for (int i = 0; i < skip; i++) {
- bs.getbits (32);
- }
-
- prev_offset = AU_start;
- AU_start = bs.bitcount ();
- if (AU_start - prev_offset != access_unit.length * 8) {
- bad_last_frame = true;
- break;
- }
-
- /* Check we have reached the end of have another catenated
- stream to process before finishing ... */
- if ((syncword = bs.getbits (16)) != AC3_SYNCWORD) {
- if (!bs.eos ()) {
- mjpeg_error_exit1 ("Can't find next AC3 frame - broken bit-stream?");
- }
- break;
- }
-
- bs.getbits (16); // CRC field
- bs.getbits (2); // Sample rate code TOOD: check for change!
- framesize_code = bs.getbits (6);
- framesize = ac3_frame_size[frequency][framesize_code >> 1];
- framesize = (framesize_code & 1) && frequency == 1 ? (framesize + 1) << 1 : (framesize << 1);
-
- access_unit.start = AU_start;
- access_unit.length = framesize;
- access_unit.PTS = static_cast < clockticks > (decoding_order) *
- static_cast < clockticks > (AC3_PACKET_SAMPLES) *
- 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[0]++;
-
- num_syncword++;
-
-
-#ifdef DEBUG_AC3_HEADERS
- /* Some stuff to generate frame-header information */
- printf ("bsid = %d\n", bs.getbits (5));
- printf ("bsmode = 0x%1x\n", bs.getbits (3));
- int acmode = bs.getbits (3);
-
- printf ("acmode = 0x%1x\n", acmode);
- if ((acmode & 0x1) && (acmode != 1))
- printf ("cmixlev = %d\n", bs.getbits (2));
- if ((acmode & 0x4))
- printf ("smixlev = %d\n", bs.getbits (2));
- if (acmode == 2)
- printf ("dsurr = %d\n", bs.getbits (2));
- printf ("lfeon = %d\n", bs.getbits (1));
- printf ("dialnorm = %02d\n", bs.getbits (5));
- int compre = bs.getbits (1);
-
- printf ("compre = %d\n", compre);
- if (compre)
- printf ("compr = %02d\n", bs.getbits (8));
- int langcode = bs.getbits (1);
-
- printf ("langcode = %d\n", langcode);
- if (langcode)
- printf ("langcod = 0x%02x\n", bs.getbits (8));
-
- while (bs.bitcount () % 8 != 0)
- bs.getbits (1);
- header_skip = (bs.bitcount () - AU_start) / 8;
-#endif
- if (num_syncword >= old_frames + 10) {
- mjpeg_debug ("Got %d frame headers.", num_syncword);
- old_frames = num_syncword;
- }
-
-
- }
- if (bad_last_frame) {
- mjpeg_error_exit1 ("Last AC3 frame ended prematurely!\n");
- }
- last_buffered_AU = decoding_order;
- eoscan = bs.eos ();
-
-}
-
-
-/// Closes the AC3 stream and prints some statistics.
-void
-AC3Stream::Close ()
-{
- stream_length = AU_start >> 3;
- mjpeg_info ("AUDIO_STATISTICS: %02x", stream_id);
- mjpeg_info ("Audio stream length %d bytes.", (int)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
-AC3Stream::OutputHdrInfo ()
-{
- mjpeg_info ("AC3 AUDIO STREAM:");
-
- mjpeg_info ("Bit rate : %8u bytes/sec (%3u kbit/sec)", bit_rate * 128, bit_rate);
-
- if (frequency == 3)
- mjpeg_info ("Frequency : reserved");
- else
- mjpeg_info ("Frequency : %d Hz", ac3_frequency[frequency]);
-
-}
-
-/**
-Reads the bytes neccessary to complete the current packet payload.
-@param to_read number of bytes to read
-@param dst byte buffer pointer to read to
-@returns the number of bytes read
- */
-unsigned int
-AC3Stream::ReadPacketPayload (uint8_t * dst, unsigned int to_read)
-{
- static unsigned int aus = 0;
- static unsigned int rd = 0;
-
- unsigned int bytes_read = bs.read_buffered_bytes (dst + 4, to_read - 4);
-
- rd += bytes_read;
- clockticks decode_time;
-
- unsigned int first_header = (new_au_next_sec || au_unsent > bytes_read)
- ? 0 : au_unsent;
-
- // BUG BUG BUG: how do we set the 1st header pointer if we have
- // the *middle* part of a large frame?
- assert (first_header <= to_read - 2);
-
-
- unsigned int syncwords = 0;
- unsigned int bytes_muxed = bytes_read;
-
- if (bytes_muxed == 0 || MuxCompleted ()) {
- goto completion;
- }
-
-
- /* Work through what's left of the current AU and the following AU's
- updating the info until we reach a point where an AU had to be
- split between packets.
- NOTE: It *is* possible for this loop to iterate.
-
- The DTS/PTS field for the packet in this case would have been
- given the that for the first AU to start in the packet.
-
- */
-
- decode_time = RequiredDTS ();
- while (au_unsent < bytes_muxed) {
- // BUG BUG BUG: if we ever had odd payload / packet size we might
- // split an AC3 frame in the middle of the syncword!
- assert (bytes_muxed > 1);
- bufmodel.Queued (au_unsent, decode_time);
- bytes_muxed -= au_unsent;
- if (new_au_next_sec)
- ++syncwords;
- aus += au->length;
- if (!NextAU ()) {
- goto completion;
- }
- new_au_next_sec = true;
- decode_time = RequiredDTS ();
- };
-
- // We've now reached a point where the current AU overran or
- // fitted exactly. We need to distinguish the latter case
- // so we can record whether the next packet starts with an
- // existing AU or not - info we need to decide what PTS/DTS
- // info to write at the start of the next packet.
-
- if (au_unsent > bytes_muxed) {
- if (new_au_next_sec)
- ++syncwords;
- bufmodel.Queued (bytes_muxed, decode_time);
- au_unsent -= bytes_muxed;
- new_au_next_sec = false;
- } else // if (au_unsent == bytes_muxed)
- {
- bufmodel.Queued (bytes_muxed, decode_time);
- if (new_au_next_sec)
- ++syncwords;
- aus += au->length;
- new_au_next_sec = NextAU ();
- }
-completion:
- // Generate the AC3 header...
- // Note the index counts from the low byte of the offset so
- // the smallest value is 1!
-
- dst[0] = AC3_SUB_STR_0 + stream_num;
- dst[1] = syncwords;
- dst[2] = (first_header + 1) >> 8;
- dst[3] = (first_header + 1) & 0xff;
-
- return bytes_read + 4;
-}
-
-
-
-/*
- * Local variables:
- * c-file-style: "stroustrup"
- * tab-width: 4
- * indent-tabs-mode: nil
- * End:
- */
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