windows - 在 CBR 音频编码中指定所需比特率的属性名称

Question

我正在尝试将“Windows Media Audio Standard”DMO 编解码器配置为以单 channel 、恒定比特率模式 (CBR) 进行压缩。不幸的是，我在 MSDN 文档中找不到如何将所需的比特率传递给编码器对象。

换句话说，我正在寻找 MFPKEY_RMAX 的等价物。这似乎确定了两遍可变比特率编码的所需比特率设置，但对于单遍 CBR 编码。

Answer 1

终于找到了。
我需要的 key 是 MF_MT_AUDIO_AVG_BYTES_PER_SECOND并记录在 here :

Choose the encoding bit rate.

For CBR encoding, you must know the bit rate at which you want to encode the stream before the encoding session begins. You must set the bit rate during while you are configuring the encoder. To do this, while you are performing media type negotiation, check the MF_MT_AUDIO_AVG_BYTES_PER_SECOND attribute (for audio streams) or the MF_MT_AVG_BITRATE attribute (for video streams) of the available output media types and choose an output media type that has the average bit rate closest to the target bit rate you want to achieve. For more information, see Media Type Negotiation on the Encoder.