Merge CV, ver=5.1; ops/methods from HV, and interface from CV where possible

[goodguy/history.git] / cinelerra-5.1 / libzmpeg3 / audio / ac3.C

diff --git a/cinelerra-5.1/libzmpeg3/audio/ac3.C b/cinelerra-5.1/libzmpeg3/audio/ac3.C
new file mode 100644 (file)
index 0000000..2310a19
--- /dev/null
+++ b/cinelerra-5.1/libzmpeg3/audio/ac3.C
@@ -0,0 +1,109 @@
+#include "../libzmpeg3.h"
+
+zaudio_decoder_ac3_t::
+audio_decoder_ac3_t()
+{
+  stream = new bits_t(0, 0);
+  state = a52_init(0);
+  output = a52_samples(state);
+}
+
+zaudio_decoder_ac3_t::
+~audio_decoder_ac3_t()
+{
+  delete stream;
+  a52_free(state);
+}
+
+
+/* Return 1 if it isn't an AC3 header */
+int zaudio_decoder_ac3_t::
+ac3_check(uint8_t *header)
+{
+  int flags, samplerate, bitrate;
+  return !a52_syncinfo(header, &flags, &samplerate, &bitrate);
+}
+
+/* Decode AC3 header */
+int zaudio_decoder_ac3_t::
+ac3_header(uint8_t *header)
+{
+  int result = 0;
+  flags = 0;
+//zmsgs("%02x%02x%02x%02x%02x%02x%02x%02x\n",
+//  header[0], header[1], header[2], header[3],
+//  header[4], header[5], header[6], header[7]);
+  result = a52_syncinfo(header, &flags, &samplerate, &bitrate);
+
+  if( result ) {
+//zmsgs("%d\n", result);
+    framesize = result;
+    channels = 0;
+
+    if( (flags & A52_LFE) != 0 )
+      ++channels;
+//zmsgs("%08x %08x\n", (flags & A52_LFE), (flags & A52_CHANNEL_MASK));
+    switch( (flags & A52_CHANNEL_MASK) ) {
+      case A52_CHANNEL: ++channels;  break;
+      case A52_MONO:    ++channels;  break;
+      case A52_STEREO:  channels += 2;  break;
+      case A52_3F:      channels += 3;  break;
+      case A52_2F1R:    channels += 3;  break;
+      case A52_3F1R:    channels += 4;  break;
+      case A52_2F2R:    channels += 4;  break;
+      case A52_3F2R:    channels += 5;  break;
+      case A52_DOLBY:   channels += 2;  break;
+      default:
+        zmsgs("unknown channel code: %08x\n", (flags & A52_CHANNEL_MASK));
+        break;
+    }
+  }
+//zmsgs("1 %d\n", channels);
+  return result;
+}
+
+
+int zaudio_decoder_ac3_t::
+do_ac3(uint8_t *zframe, int zframe_size, float **zoutput, int render)
+{
+  int output_position = 0;
+  sample_t level = 1;
+  int i, j, l;
+//zmsgs("1\n");
+  a52_frame(state, zframe, &flags, &level, 0);
+//zmsgs("2\n");
+  a52_dynrng(state, NULL, NULL);
+//zmsgs("3\n");
+  for( i=0; i < 6; ++i ) {
+    if( !a52_block(state) ) {
+      l = 0;
+      if( render ) {
+        /* Remap the channels to conform to encoders. */
+        for( j=0; j < channels; ++j ) {
+          int dst_channel = j;
+          /* Make LFE last channel. */
+          /* Shift all other channels down 1. */
+          if( (flags & A52_LFE) != 0 )
+            dst_channel = j == 0 ? channels-1 : dst_channel-1;
+          /* Swap front left and center for certain configurations */
+          switch( (flags & A52_CHANNEL_MASK) ) {
+            case A52_3F:
+            case A52_3F1R:
+            case A52_3F2R:
+              if( dst_channel == 0 ) dst_channel = 1;
+              else if( dst_channel == 1 ) dst_channel = 0;
+              break;
+          }
+
+          memmove(zoutput[dst_channel]+output_position,
+              output+l, 256*sizeof(float));
+          l += 256;
+        }
+      }
+      output_position += 256;
+    }
+  }
+
+  return output_position;
+}
+