AVFrame 的两种手动分配内部buf和data的方式

用ffmpeg的时候我们有时候需要手动为AVFrame分配内存数据，目前有两种方式，
第一种：

AVFrame *m_yuvFrame{nullptr};
uint8_t *m_outbuf{nullptr};
int m_outbuffSize{0};
m_yuvFrame = av_frame_alloc();

 // allocate buffer to store decoded frame
    AVPixelFormat av_fmt = AV_PIX_FMT_YUV420P;
    m_outbuffSize = av_image_get_buffer_size(av_fmt, width, height, 1);
    m_outbuf = static_cast<unsigned char *>(av_malloc(size_t(m_outbuffSize)));
    if (m_outbuf == nullptr) {
      LOG_ERROR("allocate buffer failed! image w:{}, h:{}", width, height);
      break;
    }

    av_image_fill_arrays(m_yuvFrame->data, m_yuvFrame->linesize, m_outbuf,
                         av_fmt, width, height, 1);

.....

  if (m_yuvFrame) {
    av_frame_unref(m_yuvFrame);
    av_frame_free(&m_yuvFrame);
    m_yuvFrame = nullptr;
  }
  
  if (m_outbuf) {
    av_free(m_outbuf);
    m_outbuf = nullptr;
  }

按照上述方式就可以将内存分配了，可以看到三个关键点：像素格式，宽和高。

第二种方式简单一点：

AVFrame *m_inFrame{nullptr};
 m_inFrame = av_frame_alloc();

  m_inFrame->width = w;
    m_inFrame->height = h;
    m_inFrame->format = AV_PIX_FMT_YUV420P;
    if (av_frame_get_buffer(m_inFrame, 0) < 0 ||
        av_frame_make_writable(m_inFrame) < 0)
      return false;

....
  if (m_inFrame) {
    av_frame_free(&m_inFrame);
    m_frame = nullptr;
  }

标签：inFrame,outbuf,data,frame,nullptr,yuvFrame,av,AVFrame,buf
来源： https://blog.csdn.net/weixin_43360707/article/details/121010807