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• Revision 67157 : utiliser pour classer les services et placer dans un groupe de ...

  26 octobre 2012, par cedric@… — Log

  utiliser &lt ;category&gt ; pour classer les services et placer dans un groupe de tête les quelques couramment usités.
  Facilite la configuration.

• How to improve the performance of Audio Queue Services when playing audio ?

  11 décembre 2014, par 谢小进

  I want to play RTMP’s H.264/AAC using FFmpeg for decoding and playing video, Audio Queue Services for playing audio. I have successfully done them all, but still some tough issues, for example high memory allocation when playing audio. I have debugged and found that Audio Queue Services lead to high memory allocation, and then crash ! Does anybody know how to improve the memory performance ? Here is my code for Audio Queue Services playing audio.

  //
  
  //  RTMPAudioPlayer.h
  
  //
  
  
  
  #import <foundation></foundation>Foundation.h>
  
  #import <audiotoolbox></audiotoolbox>AudioToolbox.h>
  
  
  
  @interface AQBuffer : NSObject
  
  
  
  @property (nonatomic) AudioQueueBufferRef buffer;
  
  
  
  @end
  
  
  
  
  
  @interface RTMPAudioPlayer : NSObject {
  
      AudioQueueRef queue;
  
      AudioStreamBasicDescription dataFormat;
  
      NSMutableArray *buffers;
  
      NSMutableArray *reusableBuffers;
  
  }
  
  
  
  - (id)initWithSampleRate:(int)sampleRate channels:(int)channels bitsPerChannel:(int)bitsPerChannel;
  
  - (void)start;
  
  - (void)stop;
  
  - (void)putData:(NSData *)data;
  
  
  
  @end
  
  
  
  
  
  
  
  
  
  //
  
  //  RTMPAudioPlayer.m
  
  //
  
  
  
  #import "RTMPAudioPlayer.h"
  
  
  
  static const int kNumberBuffers = 3;
  
  static const int kBufferSize    = 0xA000;
  
  
  
  @implementation AQBuffer
  
  
  
  @end
  
  
  
  
  
  @implementation RTMPAudioPlayer
  
  
  
  void AQOutputCallback(void *inUserData, AudioQueueRef inAQ, AudioQueueBufferRef inCompleteAQBuffer) {
  
      RTMPAudioPlayer *THIS = (__bridge RTMPAudioPlayer *)inUserData;
  
      [THIS handleAQOutputCallback:inAQ buffer:inCompleteAQBuffer];
  
  }
  
  
  
  - (void)handleAQOutputCallback:(AudioQueueRef)audioQueue buffer:(AudioQueueBufferRef)buffer {
  
      for (int i = 0; i &lt; [buffers count]; ++i) {
  
          if (buffer == [buffers[i] buffer]) {
  
              [reusableBuffers addObject:buffers[i]];
  
              break;
  
          }
  
      }
  
  }
  
  
  
  - (id)initWithSampleRate:(int)sampleRate channels:(int)channels bitsPerChannel:(int)bitsPerChannel {
  
      self = [super init];
  
      if (self) {
  
          memset(&amp;dataFormat, 0, sizeof(dataFormat));
  
          dataFormat.mSampleRate = sampleRate;
  
          dataFormat.mFormatID = kAudioFormatLinearPCM;
  
          dataFormat.mFormatFlags = kLinearPCMFormatFlagIsSignedInteger | kLinearPCMFormatFlagIsPacked;
  
          dataFormat.mBitsPerChannel = bitsPerChannel;
  
          dataFormat.mChannelsPerFrame = channels;
  
          dataFormat.mFramesPerPacket = 1;
  
          dataFormat.mBytesPerFrame = (dataFormat.mBitsPerChannel / 8) * dataFormat.mChannelsPerFrame;
  
          dataFormat.mBytesPerPacket = dataFormat.mBytesPerFrame * dataFormat.mFramesPerPacket;
  
      }
  
      return self;
  
  }
  
  
  
  - (void)start {
  
      OSStatus status = AudioQueueNewOutput(&amp;dataFormat, AQOutputCallback, (__bridge void *)self, NULL, NULL, 0, &amp;queue);
  
      if (status == noErr) {
  
          buffers = [NSMutableArray array];
  
          reusableBuffers = [NSMutableArray array];
  
          for (int i = 0; i &lt; kNumberBuffers; i++) {
  
              AudioQueueBufferRef buffer;
  
              status = AudioQueueAllocateBuffer(queue, kBufferSize, &amp;buffer);
  
              if (status == noErr) {
  
                  AQBuffer *bufferObj = [[AQBuffer alloc] init];
  
                  bufferObj.buffer = buffer;
  
                  [buffers addObject:bufferObj];
  
                  [reusableBuffers addObject:bufferObj];
  
              } else {
  
                  AudioQueueDispose(queue, true);
  
                  queue = NULL;
  
                  break;
  
              }
  
          }
  
  
  
          AudioQueueStart(queue, NULL);
  
      } else {
  
          queue = NULL;
  
      }
  
  }
  
  
  
  - (void)stop {
  
      if (queue) {
  
          AudioQueueStop(queue, true);
  
      }
  
  }
  
  
  
  - (void)putData:(NSData *)data {
  
      AQBuffer *bufferObj = [reusableBuffers firstObject];
  
      [reusableBuffers removeObject:bufferObj];
  
      AudioQueueBufferRef buffer;
  
      OSStatus status = AudioQueueAllocateBuffer(queue, kBufferSize, &amp;buffer);
  
      if (status == noErr) {
  
          bufferObj = [[AQBuffer alloc] init];
  
          bufferObj.buffer = buffer;
  
  
  
          memcpy(bufferObj.buffer->mAudioData, [data bytes], [data length]);
  
          bufferObj.buffer->mAudioDataByteSize = [data length];
  
  
  
          AudioQueueEnqueueBuffer(queue, bufferObj.buffer, 0, NULL);
  
      }
  
  }
  
  
  
  @end

• avcodec_encode_video2 coding gets H264 video frames, sent through live555 services, VLC playback, unable to display

  2 mars 2018, par donghui.R

  avcodec_encode_video2 encoding to get AVPacket H264 video frames, live555 RTSP stream service sent, client VLC play, can not be displayed. But the direct preservation of AVPacket H264 video frames is H264 files, which can be played with VLC, but it is very fast. Do not know if I need to deal with H264 video frames more closely ??