src/apps/mediaplayer/media_node_framework/audio/AudioChannelConverter.cpp

   1 /*
   2  * Copyright 2008 Stephan Aßmus <superstippi@gmx.de>
   3  * All rights reserved. Distributed under the terms of the MIT licensce.
   4  */
   5
   6
   7 #include "AudioChannelConverter.h"
   8
   9 #include <new>
  10 #include <stdio.h>
  11 #include <string.h>
  12
  13 using std::nothrow;
  14
  15
  16 //#define TRACE_AUDIO_CONVERTER
  17 #ifdef TRACE_AUDIO_CONVERTER
  18 #       define TRACE(x...)      printf(x)
  19 #else
  20 #       define TRACE(x...)
  21 #endif
  22
  23
  24 template<typename Type, typename BigType>
  25 static void
  26 convert(Type* inBuffer, Type* outBuffer, int32 inChannels, int32 outChannels,
  27         int32 frames)
  28 {
  29         // TODO: more conversions!
  30         switch (inChannels) {
  31                 case 0:
  32                         break;
  33                 case 1:
  34                         switch (outChannels) {
  35                                 case 2:
  36                                         for (int32 i = 0; i < frames; i++) {
  37                                                 *outBuffer++ = *inBuffer;
  38                                                 *outBuffer++ = *inBuffer++;
  39                                         }
  40                                         break;
  41                         }
  42                         break;
  43                 case 2:
  44                         switch (outChannels) {
  45                                 case 1:
  46                                         for (int32 i = 0; i < frames; i++) {
  47                                                 *outBuffer++
  48                                                         = (Type)((BigType)inBuffer[0] + inBuffer[1]) / 2;
  49                                                 inBuffer += 2;
  50                                         }
  51                                         break;
  52                         }
  53                         break;
  54                 default:
  55                         switch (outChannels) {
  56                                 case 2:
  57                                         for (int32 i = 0; i < frames; i++) {
  58                                                 outBuffer[0] = inBuffer[0];
  59                                                 outBuffer[1] = inBuffer[1];
  60                                                 inBuffer += outChannels;
  61                                                 outBuffer += 2;
  62                                         }
  63                                         break;
  64                         }
  65                         break;
  66         }
  67 }
  68
  69
  70 // #pragma mark -
  71
  72
  73 AudioChannelConverter::AudioChannelConverter(AudioReader* source,
  74                 const media_format& format)
  75         : AudioReader(format),
  76           fSource(source)
  77 {
  78         // TODO: check the format and make sure everything matches
  79         // except for channel count
  80 }
  81
  82
  83 AudioChannelConverter::~AudioChannelConverter()
  84 {
  85 }
  86
  87
  88 bigtime_t
  89 AudioChannelConverter::InitialLatency() const
  90 {
  91         return fSource->InitialLatency();
  92 }
  93
  94
  95 status_t
  96 AudioChannelConverter::Read(void* outBuffer, int64 pos, int64 frames)
  97 {
  98         TRACE("AudioChannelConverter::Read(%p, %Ld, %Ld)\n", outBuffer, pos, frames);
  99         status_t error = InitCheck();
 100         if (error != B_OK)
 101                 return error;
 102         pos += fOutOffset;
 103
 104         int32 inChannels = fSource->Format().u.raw_audio.channel_count;
 105         int32 outChannels = fFormat.u.raw_audio.channel_count;
 106         TRACE("   convert %ld -> %ld channels\n", inChannels, outChannels);
 107
 108         int32 inSampleSize = fSource->Format().u.raw_audio.format
 109                 & media_raw_audio_format::B_AUDIO_SIZE_MASK;
 110         int32 inFrameSize = inSampleSize * inChannels;
 111         uint8* inBuffer = new (nothrow) uint8[inFrameSize * frames];
 112
 113         TRACE("   fSource->Read()\n");
 114         status_t ret = fSource->Read(inBuffer, pos, frames);
 115         if (ret != B_OK) {
 116                 delete[] inBuffer;
 117                 return ret;
 118         }
 119
 120         // We know that both formats are the same except for channel count
 121         switch (fFormat.u.raw_audio.format) {
 122                 case media_raw_audio_format::B_AUDIO_FLOAT:
 123                         convert<float, float>((float*)inBuffer, (float*)outBuffer,
 124                                 inChannels, outChannels, frames);
 125                         break;
 126                 case media_raw_audio_format::B_AUDIO_INT:
 127                         convert<int32, int64>((int32*)inBuffer, (int32*)outBuffer,
 128                                 inChannels, outChannels, frames);
 129                         break;
 130                 case media_raw_audio_format::B_AUDIO_SHORT:
 131                         convert<int16, int32>((int16*)inBuffer, (int16*)outBuffer,
 132                                 inChannels, outChannels, frames);
 133                         break;
 134                 case media_raw_audio_format::B_AUDIO_UCHAR:
 135                         convert<uint8, uint16>((uint8*)inBuffer, (uint8*)outBuffer,
 136                                 inChannels, outChannels, frames);
 137                         break;
 138                 case media_raw_audio_format::B_AUDIO_CHAR:
 139                         convert<int8, int16>((int8*)inBuffer, (int8*)outBuffer,
 140                                 inChannels, outChannels, frames);
 141                         break;
 142         }
 143
 144         delete[] inBuffer;
 145
 146         TRACE("AudioChannelConverter::Read() done: %s\n", strerror(ret));
 147         return ret;
 148 }
 149
 150
 151 status_t
 152 AudioChannelConverter::InitCheck() const
 153 {
 154         status_t error = AudioReader::InitCheck();
 155         if (error == B_OK && !fSource)
 156                 error = B_NO_INIT;
 157         return error;
 158 }
 159
 160
 161 AudioReader*
 162 AudioChannelConverter::Source() const
 163 {
 164         return fSource;
 165 }
 166