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diff --git a/ext/mplex/videostrm_in.cc b/ext/mplex/videostrm_in.cc
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+/*
+ * inptstrm.c: Members of video stream class related to raw stream
+ * scanning and buffering.
+ *
+ * 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 "videostrm.hh"
+#include "outputstream.hh"
+
+
+
+static void
+marker_bit (IBitStream & bs, unsigned int what)
+{
+ if (what != bs.get1bit ()) {
+ mjpeg_error ("Illegal MPEG stream at offset (bits) %lld: supposed marker bit not found.",
+ bs.bitcount ());
+ exit (1);
+ }
+}
+
+
+void
+VideoStream::ScanFirstSeqHeader ()
+{
+ if (bs.getbits (32) == SEQUENCE_HEADER) {
+ num_sequence++;
+ horizontal_size = bs.getbits (12);
+ vertical_size = bs.getbits (12);
+ aspect_ratio = bs.getbits (4);
+ pict_rate = bs.getbits (4);
+ picture_rate = pict_rate;
+ bit_rate = bs.getbits (18);
+ marker_bit (bs, 1);
+ vbv_buffer_size = bs.getbits (10);
+ CSPF = bs.get1bit ();
+
+ } else {
+ mjpeg_error ("Invalid MPEG Video stream header.");
+ exit (1);
+ }
+
+ if (pict_rate > 0 && pict_rate <= mpeg_num_framerates) {
+ frame_rate = Y4M_RATIO_DBL (mpeg_framerate (pict_rate));
+ } else {
+ frame_rate = 25.0;
+ }
+
+}
+
+
+
+
+void
+VideoStream::Init (const int stream_num)
+{
+ mjpeg_debug ("SETTING video buffer to %d", muxinto.video_buffer_size);
+ MuxStream::Init (VIDEO_STR_0 + stream_num, 1, // Buffer scale
+ muxinto.video_buffer_size, 0, // Zero stuffing
+ muxinto.buffers_in_video, muxinto.always_buffers_in_video);
+ mjpeg_info ("Scanning for header info: Video stream %02x ", VIDEO_STR_0 + stream_num);
+ InitAUbuffer ();
+
+ ScanFirstSeqHeader ();
+
+ /* Skip to the end of the 1st AU (*2nd* Picture start!)
+ */
+ AU_hdr = SEQUENCE_HEADER;
+ AU_pict_data = 0;
+ AU_start = 0LL;
+
+ OutputSeqhdrInfo ();
+}
+
+//
+// Set the Maximum STD buffer delay for this video stream.
+// By default we set 1 second but if we have specified a video
+// buffer that can hold more than 1.0 seconds demuxed data we
+// set the delay to the time to fill the buffer.
+//
+
+void
+VideoStream::SetMaxStdBufferDelay (unsigned int dmux_rate)
+{
+ double max_delay = CLOCKS;
+
+ if (static_cast < double >(BufferSize ()) / dmux_rate > 1.0)
+ max_delay *= static_cast < double >(BufferSize ()) / dmux_rate;
+
+ //
+ // To enforce a maximum STD buffer residency the
+ // calculation is a bit tricky as when we decide to mux we may
+ // (but not always) have some of the *previous* picture left to
+ // mux in which case it is the timestamp of the next picture that counts.
+ // For simplicity we simply reduce the limit by 1.5 frame intervals
+ // and use the timestamp for the current picture.
+ //
+ if (frame_rate > 10.0)
+ max_STD_buffer_delay = static_cast < clockticks > (max_delay * (frame_rate - 1.5) / frame_rate);
+ else
+ max_STD_buffer_delay = static_cast < clockticks > (10.0 * max_delay / frame_rate);
+
+}
+
+//
+// Return whether AU buffer needs refilling. There are two cases:
+// 1. We have less than our look-ahead "FRAME_CHUNK" buffer AU's
+// buffered 2. AU's are very small and we could have less than 1
+// sector's worth of data buffered.
+//
+
+bool
+VideoStream::AUBufferNeedsRefill ()
+{
+ return
+ !eoscan
+ && (aunits.current () + FRAME_CHUNK > last_buffered_AU
+ || bs.buffered_bytes () < muxinto.sector_size);
+}
+
+//
+// Refill the AU unit buffer setting AU PTS DTS from the scanned
+// header information...
+//
+
+void
+VideoStream::FillAUbuffer (unsigned int frames_to_buffer)
+{
+ if (eoscan)
+ return;
+
+ last_buffered_AU += frames_to_buffer;
+ mjpeg_debug ("Scanning %d video frames to frame %d", frames_to_buffer, last_buffered_AU);
+
+ // We set a limit of 2M to seek before we give up.
+ // This is intentionally very high because some heavily
+ // padded still frames may have a loooong gap before
+ // a following sequence end marker.
+ while (!bs.eos () &&
+ bs.seek_sync (SYNCWORD_START, 24, 2 * 1024 * 1024) &&
+ decoding_order < last_buffered_AU)
+ {
+ syncword = (SYNCWORD_START << 8) + bs.getbits (8);
+ if (AU_pict_data) {
+
+ /* Handle the header *ending* an AU...
+ If we have the AU picture data an AU and have now
+ reached a header marking the end of an AU fill in the
+ the AU length and append it to the list of AU's and
+ start a new AU. I.e. sequence and gop headers count as
+ part of the AU of the corresponding picture
+ */
+ stream_length = bs.bitcount () - 32LL;
+ switch (syncword) {
+ case SEQUENCE_HEADER:
+ case GROUP_START:
+ case PICTURE_START:
+ access_unit.start = AU_start;
+ access_unit.length = (int) (stream_length - AU_start) >> 3;
+ access_unit.end_seq = 0;
+ avg_frames[access_unit.type - 1] += access_unit.length;
+ aunits.append (access_unit);
+ mjpeg_debug ("Found AU %d: DTS=%d", access_unit.dorder, (int) access_unit.DTS / 300);
+ AU_hdr = syncword;
+ AU_start = stream_length;
+ AU_pict_data = 0;
+ break;
+ case SEQUENCE_END:
+ access_unit.length = ((stream_length - AU_start) >> 3) + 4;
+ access_unit.end_seq = 1;
+ aunits.append (access_unit);
+ mjpeg_info ("Scanned to end AU %d", access_unit.dorder);
+ avg_frames[access_unit.type - 1] += access_unit.length;
+
+ /* Do we have a sequence split in the video stream? */
+ if (!bs.eos () && bs.getbits (32) == SEQUENCE_HEADER) {
+ stream_length = bs.bitcount () - 32LL;
+ AU_start = stream_length;
+ syncword = AU_hdr = SEQUENCE_HEADER;
+ AU_pict_data = 0;
+ if (opt_multifile_segment)
+ mjpeg_warn
+ ("Sequence end marker found in video stream but single-segment splitting specified!");
+ } else {
+ if (!bs.eos () && !opt_multifile_segment)
+ mjpeg_warn ("No seq. header starting new sequence after seq. end!");
+ }
+
+ num_seq_end++;
+ break;
+ }
+ }
+
+ /* Handle the headers starting an AU... */
+ switch (syncword) {
+ case SEQUENCE_HEADER:
+ /* TODO: Really we should update the info here so we can handle
+ streams where parameters change on-the-fly... */
+ num_sequence++;
+ break;
+
+ case GROUP_START:
+ num_groups++;
+ group_order = 0;
+ break;
+
+ case PICTURE_START:
+ /* We have reached AU's picture data... */
+ AU_pict_data = 1;
+
+ prev_temp_ref = temporal_reference;
+ temporal_reference = bs.getbits (10);
+ access_unit.type = bs.getbits (3);
+
+ /* Now scan forward a little for an MPEG-2 picture coding extension
+ so we can get pulldown info (if present) */
+ if (bs.seek_sync (EXT_START_CODE, 32, 64) && bs.getbits (4) == CODING_EXT_ID) {
+ /* Skip: 4 F-codes (4)... */
+ (void) bs.getbits (16);
+ /* Skip: DC Precision(2) */
+ (void) bs.getbits (2);
+ pict_struct = bs.getbits (2);
+ /* Skip: topfirst (1) frame pred dct (1),
+ concealment_mv(1), q_scale_type (1), */
+ (void) bs.getbits (4);
+ /* Skip: intra_vlc_format(1), alternate_scan (1) */
+ (void) bs.getbits (2);
+ repeat_first_field = bs.getbits (1);
+ pulldown_32 |= repeat_first_field;
+
+ } else {
+ repeat_first_field = 0;
+ pict_struct = PIC_FRAME;
+ }
+
+ if (access_unit.type == IFRAME) {
+ unsigned int bits_persec =
+ (unsigned int) (((double) (stream_length - prev_offset)) *
+ 2 * frame_rate / ((double) (2 + fields_presented - group_start_field)));
+
+ if (bits_persec > max_bits_persec) {
+ max_bits_persec = bits_persec;
+ }
+ prev_offset = stream_length;
+ group_start_pic = decoding_order;
+ group_start_field = fields_presented;
+ }
+
+ NextDTSPTS (access_unit.DTS, access_unit.PTS);
+
+ access_unit.dorder = decoding_order;
+ access_unit.porder = temporal_reference + group_start_pic;
+ access_unit.seq_header = (AU_hdr == SEQUENCE_HEADER);
+
+ decoding_order++;
+ group_order++;
+
+ if ((access_unit.type > 0) && (access_unit.type < 5)) {
+ num_frames[access_unit.type - 1]++;
+ }
+
+
+ if (decoding_order >= old_frames + 1000) {
+ mjpeg_debug ("Got %d picture headers.", decoding_order);
+ old_frames = decoding_order;
+ }
+
+ break;
+
+
+
+ }
+ }
+ last_buffered_AU = decoding_order;
+ num_pictures = decoding_order;
+ eoscan = bs.eos ();
+}
+
+void
+VideoStream::Close ()
+{
+
+ bs.close ();
+ stream_length = (unsigned int) (AU_start / 8);
+ for (int i = 0; i < 4; i++) {
+ avg_frames[i] /= num_frames[i] == 0 ? 1 : num_frames[i];
+ }
+
+ comp_bit_rate = (unsigned int)
+ ((((double) stream_length) / ((double) fields_presented)) * 2.0
+ * ((double) frame_rate) + 25.0) / 50;
+
+ /* Peak bit rate in 50B/sec units... */
+ peak_bit_rate = ((max_bits_persec / 8) / 50);
+ mjpeg_info ("VIDEO_STATISTICS: %02x", stream_id);
+ mjpeg_info ("Video Stream length: %11llu bytes", stream_length / 8);
+ mjpeg_info ("Sequence headers: %8u", num_sequence);
+ mjpeg_info ("Sequence ends : %8u", num_seq_end);
+ mjpeg_info ("No. Pictures : %8u", num_pictures);
+ mjpeg_info ("No. Groups : %8u", num_groups);
+ mjpeg_info ("No. I Frames : %8u avg. size%6u bytes", num_frames[0], avg_frames[0]);
+ mjpeg_info ("No. P Frames : %8u avg. size%6u bytes", num_frames[1], avg_frames[1]);
+ mjpeg_info ("No. B Frames : %8u avg. size%6u bytes", num_frames[2], avg_frames[2]);
+ mjpeg_info ("No. D Frames : %8u avg. size%6u bytes", num_frames[3], avg_frames[3]);
+ mjpeg_info ("Average bit-rate : %8u bits/sec", comp_bit_rate * 400);
+ mjpeg_info ("Peak bit-rate : %8u bits/sec", peak_bit_rate * 400);
+
+}
+
+
+
+
+/*************************************************************************
+ OutputSeqHdrInfo
+ Display sequence header parameters
+*************************************************************************/
+
+void
+VideoStream::OutputSeqhdrInfo ()
+{
+ const char *str;
+
+ mjpeg_info ("VIDEO STREAM: %02x", stream_id);
+
+ mjpeg_info ("Frame width : %u", horizontal_size);
+ mjpeg_info ("Frame height : %u", vertical_size);
+ if (aspect_ratio <= mpeg_num_aspect_ratios[opt_mpeg - 1])
+ str = mpeg_aspect_code_definition (opt_mpeg, aspect_ratio);
+ else
+ str = "forbidden";
+ mjpeg_info ("Aspect ratio : %s", str);
+
+
+ if (picture_rate == 0)
+ mjpeg_info ("Picture rate : forbidden");
+ else if (picture_rate <= mpeg_num_framerates)
+ mjpeg_info ("Picture rate : %2.3f frames/sec",
+ Y4M_RATIO_DBL (mpeg_framerate (picture_rate)));
+ else
+ mjpeg_info ("Picture rate : %x reserved", picture_rate);
+
+ if (bit_rate == 0x3ffff) {
+ bit_rate = 0;
+ mjpeg_info ("Bit rate : variable");
+ } else if (bit_rate == 0)
+ mjpeg_info ("Bit rate : forbidden");
+ else
+ mjpeg_info ("Bit rate : %u bits/sec", bit_rate * 400);
+
+ mjpeg_info ("Vbv buffer size : %u bytes", vbv_buffer_size * 2048);
+ mjpeg_info ("CSPF : %u", CSPF);
+}
+
+//
+// Compute PTS DTS of current AU in the video sequence being
+// scanned. This is is the PTS/DTS calculation for normal video only.
+// It is virtual and over-ridden for non-standard streams (Stills
+// etc!).
+//
+
+void
+VideoStream::NextDTSPTS (clockticks & DTS, clockticks & PTS)
+{
+ if (pict_struct != PIC_FRAME) {
+ DTS = static_cast < clockticks > (fields_presented * (double) (CLOCKS / 2) / frame_rate);
+ int dts_fields = temporal_reference * 2 + group_start_field + 1;
+
+ if (temporal_reference == prev_temp_ref)
+ dts_fields += 1;
+ PTS = static_cast < clockticks > (dts_fields * (double) (CLOCKS / 2) / frame_rate);
+ access_unit.porder = temporal_reference + group_start_pic;
+ fields_presented += 1;
+ } else if (pulldown_32) {
+ int frames2field;
+ int frames3field;
+
+ DTS = static_cast < clockticks > (fields_presented * (double) (CLOCKS / 2) / frame_rate);
+ if (repeat_first_field) {
+ frames2field = (temporal_reference + 1) / 2;
+ frames3field = temporal_reference / 2;
+ fields_presented += 3;
+ } else {
+ frames2field = (temporal_reference) / 2;
+ frames3field = (temporal_reference + 1) / 2;
+ fields_presented += 2;
+ }
+ PTS = static_cast < clockticks >
+ ((frames2field * 2 + frames3field * 3 + group_start_field +
+ 1) * (double) (CLOCKS / 2) / frame_rate);
+ access_unit.porder = temporal_reference + group_start_pic;
+ } else {
+ DTS = static_cast < clockticks > (decoding_order * (double) CLOCKS / frame_rate);
+ PTS = static_cast < clockticks >
+ ((temporal_reference + group_start_pic + 1) * (double) CLOCKS / frame_rate);
+ fields_presented += 2;
+ }
+
+}
+
+
+
+
+
+/*
+ * Local variables:
+ * c-file-style: "stroustrup"
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
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