Set H.264 options

  • Article

You can use the H.264 options in Microsoft Expression Encoder to refine the parameters for your MP4, or H.264, encoding.

Important

The option of choosing MP4 as an output format or choosing H.264 as a codec is available only in Expression Encoder with IIS Smooth Streaming.

To set H.264 options

  1. Click the Encode tab. If you can't see the Encode tab, on the Window menu, click Encode.

  2. Set your H.264 options in the Profile panel according to the following guidelines:

    • Complexity   Specifies the number of frames that the compressor will search in order to find redundancies. The higher the value, the more precise the encoding, but the more complex the decoding.

    • Number of Reference Frames   Specifies the number of P and B frames to create in each Group of Pictures (GOP).

    • Search range   Specifies the size of the area the codec will search for an element of a frame that may have moved from a previous frame. Generally, the more fast motion that your video contains, the larger a range value you should specify.

      Note

      Larger range values require more CPU time.

    • Entropy Mode   Specifies the type of entropy, or H.264, coding that you want. Context-adaptive binary arithmetic coding (CABAC) is a lossless, complex encoding method. It is more complex than context-adaptive variable-length encoding (CAVLC), but it may take longer to encode than CAVLC. Although CAVLC is less complex than CABAC, it is still a high-quality alternative.

    • ME Partition Level   Defines the detail of the motion estimation calculation for the interpredicted frames. The smaller the partition level, the better the compression quality. "ME" stands for Motion Estimation.

    • Threads Used   Specifies the number of threads Expression Encoder will use to encode the media. This helps you to take advantage of encoding on multicore machines. Utilizing multiple cores will help decrease your encoding time. Which values display in this menu depends upon the number of cores that your machine has. When encoding, Expression Encoder will horizontally split the video into the number of threads that you specify, and subsequently uses a separate core to encode each thread. In general, the larger the height of your video, the more threads you should use. Click Auto to have Expression Encoder set the optimum thread value.

    • Force 16 pixel dimensions   Constrains the width and height values of the video to multiples of 16. Codecs perform better when the video dimensions are a multiple of 16. Deselecting this setting constrains the width and height values to multiples of 4.

    • In Loop Filter   Reduces blocking artifacts during encoding. This option is especially effective for video that contains fast motion or quick edits.

    • RD Optimization   This is also known as rate-distortion optimization. Determines the ideal balance between encoding quality and the bits required to achieve that quality. Selecting this option will help to maximize the quality of your final encoded media for the bitrate you have specified, but will also increase your encoding time.