在0.7.5.4710版本中, MediaCoder新增了将视频采集设备作为一个任务的功能，换句话说，现在可以简单快捷地将摄像头或者其它DirectShow视频采集设备的画面用MediaCoder直接编码了。点击“添加”按钮即可看到一个新的“添加视频采集设备”的选项。 Read the rest of this entry »

Finally we can have multiple files processed simultaneously in MediaCoder with the new job-level parallelization support. Those who have a processor with 8 or 16 cores can now unleash the power of their processor. As MediaCoder is not just a simple GUI front-end which only invokes a command line encoder wait sits there waiting for the encoder to complete, instead it distribute frame data and the audio samples from decoders to encoders, the job-level parallelization is not that easy to add from the old design. In order to add this feature, large amount of the code has been rewritten. Finally it works after several weeks’ efforts, though it might still be experimental for a while. The number of the maximum parallelized jobs is limited to 4 at the moment. So feedbacks welcomed!

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最新的MediaCoder iPod专用版包含了iPad视频配置。该版本的64位版也同时发布。

iPad支持的视频格式

* H.264视频最高720p, 每秒30帧, Main Profile level 3.1, 音频为AAC-LC音频最高160 Kbps, 48kHz, 以mp4或者.mov格式封装;
* MPEG-4视频最高码率2.5 Mbps, 最高640×480分辨率 pixels, 每秒30帧, Simple Profile, 音频为AAC-LC音频最高160 Kbps, 48kHz, 以mp4或者.mov格式封装
* Motion JPEG (M-JPEG) 最高35 Mbps, 最高1280×720分辨率, 每秒30帧, 音频为ulaw, PCM音频, 以avi格式封装

点击此处立即下载最新MediaCoder iPod/iPhone/iPad专用版

在最新的Build 4560中新增了设置影音编解码器的处理器亲和度（Processor Affinity）参数。通过设置代表所有处理器或处理器核心的复选框，可以控制哪些处理器或者核心被使用，哪些不被使用。例如，在一个四核处理器的系统上，你会看到有四个复选框是可选的，如果一个复选框没有被选中，那相应的处理器或者核心就不会被使用。当你的处理器有很多核心时，这个功能就比较有用了。你可以自行分配解码器和编码器所使用的核心，也可以预留一些核心供其他应用使用。

请注意以下几个小贴士：

• 即使所有的复选框被选中，这也不意味着你的多核处理器能被100%使用。这还取决于编解码器的多线程支持程度。
• 和优先级设置不同，多核分配设置在下一个任务开始后才会生效。

MediaCoder is improving all the time even if the version number keep the same. This time there are some major changes, so let’s increase the number after nearly 10 months. I’ve spent lots of time to prepare the release of 0.7. Let me briefly recall what has been changed. Read the rest of this entry »

Item grouping feature is added since build 4260. By selecting multiple items in the list and choosing Group from menu (right click an item to pop up), the items will be marked as the same group ID. During processing, they will be joined into one file. The grouping feature also prepares for the upcoming support for multi-track transcoding. The join mode is removed since then.

Item grouping in MediaCoder

Windows Media encoding is proved in the latest build 4224. Previously, when MediaCoder encoding Windows Media with Microsoft Windows Media Format component, audio and video data are encoded and muxed in one thread (despite the possibility that the component may have its multi-threading approach underlying). Now audio and video are encoded in separated threads, and the encoded streams are multiplexed after encoding process. This will eliminate some WMV encoding problem and bring in better encoding performance on dual-core processors as well as better container flexibility. If you experience problems with the new mechansim, please report.

A new task mode, benchmark mode, has been added since build 4210. In this mode, MediaCoder can be used to benchmark your hardware with media transcoding based on the your transcoding settings. During the process, the media content will be transcoded as in normal mode. The difference is there is no file created on hard drive and a benchmark result will be shown on the end of the procedure.

The steps to perform transcoding benchmark are as simple as following:

1. Add files used for benchmarking
2. Set up transcoding parameters
3. Set task mode to “Benchmark”
4. Click Start button to start benchmarking

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