Question

我正在使用Windows Media Foundation编码H264视频。（我使用MFNet Wrapper通过C＃使用它。）

视频编码效果很好。我拿出带有H264视频的MP4。

现在我尝试添加音频。我想从内存中传入未压缩的PCM，然后输出编码的AAC。我将audiostream添加到我的SinkWriter中。 ö但在致电SetInputMediaType时，我得到MF_E_INVALIDMEDIATYPE。

为什么？

这是我的代码：

IMFMediaType audioTypeOut, audioTypeIn, videoTypeOut, videoTypeIn;
IMFSinkWriter sinkWriter;

Check = MFCreateSinkWriterFromURL(outputFile.Replace(".avi",".mp4"), null, attributes, out sinkWriter); // the assignment to "Check" throws an exception if a method fails.

//[ ... setup video input & output - works perfectly ...]
Check = sinkWriter.AddStream(videoTypeOut, out videoStreamIndex);
Check = sinkWriter.SetInputMediaType(videoStreamIndex, videoTypeIn, null);

// Now setup Audio:
// Input PCM from memory
Check = MFExtern.MFCreateMediaType(out audioTypeIn);
Check = audioTypeIn.SetGUID(MFAttributesClsid.MF_MT_MAJOR_TYPE, MFMediaType.Audio);
Check = audioTypeIn.SetGUID(MFAttributesClsid.MF_MT_SUBTYPE, MFMediaType.PCM); // this .PCM enum value is equal to MFAudioFormat_PCM in the C++ api (I checked)
Check = audioTypeIn.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_NUM_CHANNELS, 2);
Check = audioTypeIn.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_SAMPLES_PER_SECOND, 44100);
Check = audioTypeIn.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_BLOCK_ALIGNMENT, 4);
Check = audioTypeIn.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_AVG_BYTES_PER_SECOND, 44100 * 4);
Check = audioTypeIn.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_BITS_PER_SAMPLE, 16);
Check = audioTypeIn.SetUINT32(MFAttributesClsid.MF_MT_ALL_SAMPLES_INDEPENDENT, 1);

// and output AAC to the MP4 file
Check = MFExtern.MFCreateMediaType(out audioTypeOut);
Check = audioTypeOut.SetGUID(MFAttributesClsid.MF_MT_MAJOR_TYPE, MFMediaType.Audio);
Check = audioTypeOut.SetGUID(MFAttributesClsid.MF_MT_SUBTYPE, MFMediaType.AAC);
Check = audioTypeOut.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_NUM_CHANNELS, 2);
Check = audioTypeOut.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_SAMPLES_PER_SECOND, 44100);
Check = audioTypeOut.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_BITS_PER_SAMPLE, 16);
Check = audioTypeOut.SetUINT32(MFAttributesClsid.MF_MT_ALL_SAMPLES_INDEPENDENT, 0);

// pass it to the sinkWriter
Check = sinkWriter.AddStream(audioTypeOut, out audioStreamIndex);
Check = sinkWriter.SetInputMediaType(audioStreamIndex, audioTypeIn, null); // this call fails

现在，当我尝试传入AAC时，设置代码完美无缺。让我觉得我错误配置PCM IMFMediaType，但我无法发现错误。

Answer 1

音频媒体类型可以像这样初始化：

io.on('connection', function(client) {
    client.on('online', function(data) {
        socket_api.user_online(data.user_id, function (err,res){
            if (err) {
                client.emit ('error',err);
            } else {
                console.log ("client connected")
                client.emit ('online_response', res);
            }

        });
        // client.emit('messages', 'Hello from server');
    });
    client.on('disconnect', function (data){
        console.log ("Client disconnected");
    });
});

将导出其他属性，并且在原始代码段中错误使用// Input PCM from memory Check = MFExtern.MFCreateMediaType(out audioTypeIn); Check = audioTypeIn.SetGUID(MFAttributesClsid.MF_MT_MAJOR_TYPE, MFMediaType.Audio); Check = audioTypeIn.SetGUID(MFAttributesClsid.MF_MT_SUBTYPE, MFMediaType.PCM); Check = audioTypeIn.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_NUM_CHANNELS, 2); Check = audioTypeIn.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_SAMPLES_PER_SECOND, 44100); Check = audioTypeIn.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_BITS_PER_SAMPLE, 16); // and output AAC to the MP4 file Check = MFExtern.MFCreateMediaType(out audioTypeOut); Check = audioTypeOut.SetGUID(MFAttributesClsid.MF_MT_MAJOR_TYPE, MFMediaType.Audio); Check = audioTypeOut.SetGUID(MFAttributesClsid.MF_MT_SUBTYPE, MFMediaType.AAC); Check = audioTypeOut.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_NUM_CHANNELS, 2); Check = audioTypeOut.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_SAMPLES_PER_SECOND, 44100); Check = audioTypeOut.SetUINT32(MFAttributesClsid.MF_MT_AUDIO_BITS_PER_SAMPLE, 16);会阻止编解码器的初始化。

Media Foundation MP4编码：IMFSinkWriter不接受PCM输入

1 个答案: