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Frequently asked questions

  1. Is the new Windows Media Audio version 8 codec compatible with previous versions of the codec?

    Yes. Content encoded with the Windows Media Audio version 8 codec can be decoded by previous versions of the Windows Media Audio codec.

  2. Can I set up a live broadcast with Windows Media 8 Encoding Utility?

    No. Windows Media 8 Encoding Utility is intended for creating on-demand files only.

  3. Can I use extended .avi files with Windows Media 8 Encoding Utility?

    Yes. Windows Media 8 Encoding Utility supports the extended .avi format specification and can encode .avi files that are larger than 2 gigabytes (GB).

  4. Can I edit profiles with the Windows Media Encoder 7 Profile Manager feature and then use those edited profiles with Windows Media 8 Encoding Utility?

    No. But you can create your own profiles using a configuration file. See Using configuration files for more information.

  5. What kind of compression is applied if I don't specify a profile or optional parameters in my encoding command?

    Windows Media 8 Encoding Utility will use the defaults for each setting. For example, the Windows Media Audio version 8 and Windows Media Video version 8 codecs would be used, the frame rate would match that of the input source, and the audio and video bit rates would be 60 and 80 kilobits per second (Kbps), respectively.

  6. What's the difference between the new codecs and those that were included with Windows Media Encoder 7?

    The Windows Media Audio version 8 codec improves audio quality by 30 to 50 percent over the Windows Media Audio version 7 codec. For example, it offers the same audio quality as .mp3 but in a file that is one-third the size. It can also provide audio streams that are near CD-quality over a 48 Kbps connection. The Windows Media Video version 8 codec provides video quality improvements of 20 to 30 percent for broadband Internet users compared with the Windows Media Video version 7 codec.

  7. Can I transcode compressed Windows Media files with .wma and .wmv file name extensions in order to achieve a different bit rate?

    No. If you want to encode your audio or video at a different bit rate than what you encoded the first time, encode the original uncompressed source file (with a .wma, .wmv, .avi, or .wav file name extension) again and specify the bit rate you want with the –v_bitrate option for video or the –a_setting option for audio.

  8. I set the –v_bitrate in one- and two-pass constant bit rate and bit-rate-based variable bit rate modes (-v_mode 0, 1, and 3), and the bit rate of the compressed clip is significantly lower than what I specified. Is this an error?

    No. If the clip, or some segment of the clip, is easy to encode for the target bit rate (for example, the bit rate setting is very high and the resolution is low) then the codec will not require all of the available bandwidth to compress the content.

  9. I set the –v_bitrate in bit-rate-based variable bit rate mode (-v_mode 3), and the bit rate of the compressed clip is significantly higher than what I specified. Is this an error?

    No. Frames are not dropped when you encode using the –v_mode 3 option. Therefore, if the clip, or some segment of the clip, is difficult to encode for the target bit rate (for example, the bit rate setting is low and the resolution is high) then the codec will require more bandwidth to compress the content.

  10. In what order does Windows Media 8 Encoding Utility clip, preprocess, and resize my content?

    Clipping is the first step and is performed on the source. By clipping first, your encoding process will be more efficient because you eliminate any unwanted portions of the video before encoding them. Preprocessing, such as applying deinterlacing or inverse telecine filters, comes second, followed by setting the output size of the encoded video.

  11. What is the difference between the encoding modes in Windows Media Encoder 7 and Windows Media 8 Encoding Utility?

    Windows Media 8 Encoding Utility enables you to perform two-pass constant bit rate video encoding and variable bit rate encoding that is either based on quality or bit rate.

  12. Can I add the Windows Media Audio version 8 and Windows Media Video version 8 codecs to Windows Media Encoder 7?

    No. Windows Media Encoder 7 does not currently support Windows Media Audio version 8 and Windows Media Video version 8 codecs. The next version of Windows Media Encoder will support these or other future versions of the codecs, as well as two-pass constant bit rate video encoding and quality- and bit-rate-based variable bit rate encoding.

  13. Can I use Windows Media 8 Encoding Utility to encode a multiple bit rate file in order to stream my content to users who have various connection speeds?

    No. Windows Media 8 Encoding Utility does not support multiple bit rate encoding. Windows Media Encoder 7 does support multiple bit rate encoding, and includes several profiles to suit your needs.

  14. Should I convert my .mp3 files to .wav files in order to encode them with Windows Media 8 Encoding Utility?

    No. Converting from .mp3 to .wav causes quality degradation. Use Windows Media Encoder 7 to encode your .mp3 files. Use the original uncompressed content when encoding with Windows Media 8 Encoding Utility.

  15. When playing back my encoded audio in Windows Media Player 7, I hear popping sounds. I don't hear these sounds when playing the same audio in Windows Media Player 6.4. What is causing this?

    The popping sound you hear is a brief discontinuity in the audio track caused by a reading error in Windows Media Player 7. This problem is not common and is usually inaudible. Until an update is available to fix the problem, use Windows Media Player 6.4 to play any clips where the popping sound is noticeable.

  16. I used the -v_quality setting to set my image quality at 95 and then 96. I achieved the same result with both settings. Is this normal?

    Yes. Some of the -v_quality settings are mapped internally to the same image quality value. To see a change in your image quality, increase or decrease your -v_quality setting by larger increments.

  17. The statistic showing the amount of buffer that was used during my encoding session differs from the -v_buffer value that I set. Why?

    If you set a large buffer but are encoding content that is not very complex, the codecs may not use all of the buffer space that was allocated. In the rare case that you set a very small buffer, the codecs may need a larger buffer space than what you allocated. The effective buffering delay is either the buffer that you set or that the codecs actually used, whichever is larger.

  18. Why is my encoded video upside down when I play it back in Windows Media Player?

    Occasionally, encoded video will be upside down when it is played in Windows Media Player because capture card drivers interpret the packed YUV file format in different ways.

    Windows Media 8 Encoding Utility enables you to set a registry key that will flip the video before encoding it so that it displays correctly. By default this feature is disabled. To enable this feature, use the registry editor to locate the registry key HKEY_CURRENT_USER\SOFTWARE\Microsoft\Scrunch\WMVideo\Vertical Flip Packed YUV, and then set the DWORD value of this registry key to 1.

    Note   You should only edit the registry if you are an advanced user. It is strongly recommended that you do not edit any other values in the registry. For more information about the registry, see Windows Help.


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