diff options
Diffstat (limited to 'command/audio.cpp')
| -rw-r--r-- | command/audio.cpp | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/command/audio.cpp b/command/audio.cpp new file mode 100644 index 0000000..bd35ddc --- /dev/null +++ b/command/audio.cpp @@ -0,0 +1,184 @@ +/* + * audio.cpp: A program for the Video Disk Recorder + * + * See the README file for copyright information and how to reach the author. + * + * $Id$ + */ + +#include "audio.h" + +cMarkAdAudio::cMarkAdAudio(MarkAdContext *maContext) +{ + macontext=maContext; + mark.Comment=NULL; + mark.Position=0; + mark.Type=0; + channels=0; +#if 0 + lastiframe_gain=-ANALYZEFRAMES; +#endif + lastiframe_silence=-1; +} + +cMarkAdAudio::~cMarkAdAudio() +{ + ResetMark(); +} + +void cMarkAdAudio::ResetMark() +{ + if (mark.Comment) free(mark.Comment); + mark.Comment=NULL; + mark.Position=0; + mark.Type=0; +} + +bool cMarkAdAudio::AddMark(int Type, int Position, const char *Comment) +{ + if (!Comment) return false; + if (mark.Comment) + { + int oldlen=strlen(mark.Comment); + mark.Comment=(char *) realloc(mark.Comment,oldlen+10+strlen(Comment)); + if (!mark.Comment) + { + mark.Position=0; + return false; + } + strcat(mark.Comment," ["); + strcat(mark.Comment,Comment); + strcat(mark.Comment,"]"); + } + else + { + mark.Comment=strdup(Comment); + } + mark.Position=Position; + mark.Type=Type; + return true; +} + +bool cMarkAdAudio::SilenceDetection() +{ + if (!macontext->Audio.Data.Valid) return false; + if (lastiframe_silence==lastiframe) return false; // we already detected silence for this frame + + int samples=macontext->Audio.Data.SampleBufLen/ + sizeof(*macontext->Audio.Data.SampleBuf)/ + macontext->Audio.Info.Channels; + + short left,right; + int lowvalcount=0; + for (int i=0; i<samples; i++) + { + left=macontext->Audio.Data.SampleBuf[0+(i*2)]; + right=macontext->Audio.Data.SampleBuf[1+(i*2)]; + + if ((abs(left)+abs(right))<CUT_VAL) + { + lowvalcount++; + if (lowvalcount>MIN_LOWVALS) + { + lastiframe_silence=lastiframe; + return true; + } + } + else + { + lowvalcount=0; + } + } + return false; +} + +#if 0 +bool cMarkAdAudio::AnalyzeGain() +{ + if (!macontext->Audio.Data.Valid) return false; + + int samples=macontext->Audio.Data.SampleBufLen/ + sizeof(*macontext->Audio.Data.SampleBuf)/ + macontext->Audio.Info.Channels; + + double left[samples]; + double right[samples]; + + for (int i=0; i<samples; i++) + { + left[i]=macontext->Audio.Data.SampleBuf[0+(i*2)]; + right[i]=macontext->Audio.Data.SampleBuf[1+(i*2)]; + } + + if ((lastiframe-lastiframe_gain)>ANALYZEFRAMES) + { + if (lastiframe_gain>0) + { + double dgain,gain = audiogain.GetGain(); + dgain=gain-lastgain; + printf("%05i %+.2f db %+.2f db\n",lastiframe_gain,gain,lastgain); + lastgain=gain; + } + audiogain.Init(macontext->Audio.Info.SampleRate); + lastiframe_gain=lastiframe; + } + if (audiogain.AnalyzeSamples(left,right,samples,2)!=GAIN_ANALYSIS_OK) + { + lastiframe_gain=-ANALYZEFRAMES; + } + + return true; +} +#endif + +bool cMarkAdAudio::ChannelChange(int a, int b) +{ + if ((a==0) || (b==0)) return false; + if (a!=b) return true; + return false; +} + +MarkAdMark *cMarkAdAudio::Process(int LastIFrame) +{ + ResetMark(); + if (!LastIFrame) return NULL; + lastiframe=LastIFrame; + +#if 0 + AnalyzeGain(); +#endif + if (macontext->Audio.Options.AudioSilenceDetection) + { + if (SilenceDetection()) + { + char *buf=NULL; + if (asprintf(&buf,"audio channel silence detecion (%i)",lastiframe)!=-1) + { + AddMark(MT_SILENCECHANGE,lastiframe,buf); + free(buf); + } + } + } + + if (ChannelChange(macontext->Audio.Info.Channels,channels)) + { + char *buf=NULL; + if (asprintf(&buf,"audio channel change from %i to %i (%i)", channels, + macontext->Audio.Info.Channels,lastiframe)!=-1) + { + if (macontext->Audio.Info.Channels>2) + { + AddMark(MT_CHANNELSTART,lastiframe,buf); + } + else + { + AddMark(MT_CHANNELSTOP,lastiframe,buf); + } + free(buf); + } + } + + channels=macontext->Audio.Info.Channels; + return &mark; +} + |