News and Notes related to Digital Media Transcription, Analysis, and Captioning.
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  • What is a Codec Anyway?

    Posted on November 13th, 2014 Alex No comments

    If you work at all with digital video, you’re bound to run into issues of media compatibility. What makes a video incompatible? Will it work in InqScribe? It’s a complicated subject. In this post, we’ll explain a few key terms that should help you understand how digital video works (and sometimes, how it doesn’t work).

    Codec

    Codec stands for coder/decoder, and it does just that. Raw video tends to take up large amounts of storage, and codecs allow us to shrink down the file size, usually without losing too much quality. Codecs achieve this by taking the raw video data and encoding it into a shorthand. Once encoded, codecs also play a role in decoding this shorthand.

    Note that codecs are independent of a video’s file extension. So, .mp4, .avi, .mov, etc. are not codecs. A .mp4 file could use a H.264/AVC or MPEG-4 Part 2 codec, for example. You can see which codecs are supported by QuickTime via Apple’s support page here. To check which codecs you have available in Windows Media Player, follow Microsoft’s directions here (use drop-down bar on right to select your version of Windows).

    Although some are more popular than others, there are dozens of different codecs out there. Since each uses a unique coding language, it’s important to use codecs that are compatible with your workflow (and that you have access to- some codecs are proprietary). What should you do if you come across an incompatible codec? Transcode! More on that in a bit…

    Container

    QuickTime "movie could not be opened" message

    Look familiar?

    As its name suggests, a container file packages compressed video data. Containers identify and sort out codecs, which are the ones doing the actual compressing. Most common video containers are compatible with multiple codecs, so don’t assume one container is always going to have the same codec.

    Chances are, you’re more familiar with containers than you are with codecs. They’re more visible because the file extension is often associated with the container. A file with the name “Sample.mp4” has a file extension of “.mp4”, which indicates the MP4 container. Other examples of containers include AVI, MPEG-2, FLV, and RM to name a few.

    In addition to a file’s codec, programs such as QuickTime and Windows Media Player will have their own specs for which containers they support. So, to drive this home: just because you have a compatible container for your video file, it doesn’t mean you have a compatible codec. And vise-versa.

    Transcode

    To transcode is to convert from one encoding to another. When you transcode a file, you are essentially changing a video’s codec or its container, perhaps both. The terms “transcoding” and “converting” are generally used interchangeably.

    It’s worth noting that transcoding a file will result in some loss of quality. The extent of this may or may not be noticeable.

    If you’re interested in transcoding, check out our blog post on Media Conversion Tools for more information.

    Mux

    To “mux” a file is to combine multiple channels into one. When referring to video files, these channels are typically audio, video, and/or subtitle tracks. Muxing is useful when compiling several of these tracks into one output, such as when you’re creating a DVD or Blu-ray disk.

    Since not all media player can process muxed files, you might not always want a file to be muxed. This is when demuxing comes into play.

    Demux

    To demux a file is to extract the individual tracks back into their separate channels. Demuxing is useful when you come across an unsupported muxed file.

    Since transcoding will rewrite a file’s video and audio data, it can actually be used to demux a file. So, when in doubt, transcoding can solve several different problems associated with incompatibility.


    Understanding these terms and concepts should equip you to deal with incompatible media. And remember, if you’re ever having trouble getting InqScribe to recognize your media files, just send an email to support@inqscribe.com.

  • TIP: How Can I Convert My “[00:01:23.29]” Timecodes to “00:01:23.29” (Remove Brackets)?

    Posted on August 6th, 2009 ben No comments

    I have an existing InqScribe transcript that uses bracketed timecodes: [00:01:23.29]

    I want to use unbracketed timecodes: 00:01:23.29

    Here’s how you can do the conversion:

    1. Open the existing transcript in InqScribe.

    2. Select “Transcript->Transcript Settings…” from the menu bar.

    3. Under the “Inserted Timecode Format:” select “00:01:23.29” from the popup menu.

    4. Check the “Recognize Unbracketed Timecodes” checkbox.

    5. Click “OK” to close the window.

    6. Select “Transcript->Adjust Timecodes…” from the menu bar.

    7. Leave the “Adjustment:” field blank, and click “Adjust.”  This will reformat all of your timecodes to the unbracketed format.

    To change ALL of your future transcripts to use the unbracketed timecodes…

    …On a Mac:

    1. Select “InqScribe->Preferences…” from the menu bar.

    2. Click on the “New Document” tab at the top of the “InqScribe Preferences” window.

    3. Under the “Inserted Timecode Format:” select “00:01:23.29” from the popup menu.

    4. Check the “Recognize Unbracketed Timecodes” checkbox.

    …On Windows:

    1. Select “Edit->Options…” from the menu bar.

    2. Click on the “New Document” tab at the top of the “InqScribe Preferences” window.

    3. Under the “Inserted Timecode Format:” select “00:01:23.29” from the popup menu.

    4. Check the “Recognize Unbracketed Timecodes” checkbox.

    By the way, there are a number of other formats that you can use as well.

  • TIP: How to Bold Timecodes in Microsoft Word

    Posted on August 5th, 2009 ben No comments

    InqScribe currently does not support bold text.  However, you can use Microsoft Word’s “Find and Replace” feature to bold text.  Here’s how you can do that:

    1. Export your transcript to Microsoft Word.  (You can just cut and paste.)

    2. Select “Edit->Replace…”.

    3. Click on the triangle next to the “Replace All” button to reveal the advanced options.

    4. Check the “Use wildcards” option.

    5. Under “Find what:” enter this:

    [^#^#:^#^#:^#^#.^#^#]

    NOTE this assumes that you’re using the default timecode format.  If you’re using another timecode format, just format the colons and periods accordingly.  Each “^#” matches a digit.  For example, if your timecode looks like “<00:00:00.00>” use “<^#^#:^#^#:^#^#.^#^#>”.

    6. Click in the “Replace with:” field.

    7. From the popup menu at the bottom of the window called “Format” select “Font…” and then click on “Bold”, then click “OK”.  The “Replace with:” field should say “Format: Font:Bold” underneath it.

    8. Click on “Find Next” to make sure it works — does Word find the first timecode?  If so, then try clicking “Replace” to see if it bolds it.  If it does, then you can use “Replace All” to bold all of the timecodes.