Authors are strongly encouraged to adhere to the following guidelines when preparing multimedia files:
- The acceptable file formats outlined above are playable using standard media players, such as QuickTime and Windows Media Player. Media players should be used to check file properties and image/sound quality prior to submission. For video submissions, fonts, lines, and image details should be of sufficient size and weight to be visible when played at half size.
- Attention should be paid to the file size to make download time reasonable since streaming formats are not acceptable for submission at this time. A recommended target size for each multimedia file is 3–5 MB.
- Authors are encouraged to use one of the accepted compression codecs to minimize file sizes.
- Animations must be formatted into a standard video file.
*Please note the below guidelines/considerations that apply to all multimedia submissions.
Acceptable file formats include PCM (.pcm), WAV (.wav), AIFF (.aif), and MP3 (.mp3) at 128 KB or greater.
*Please note the below guidelines/considerations that apply to all multimedia submissions.
Acceptable file formats include QuickTime nonstreaming video (.qt or .mov), MPEG (.mpg), and DV (.dv). The preferred formats are .mov, and .mpg. Details about each of these file formats are outlined below. Note that AVI files are no longer a recommended file format, because the wide variety of AVI codecs cannot be reliably archived.
Authors must insert a representative “still” image, taken from the video, in the manuscript as a figure. This still image is not intended to convey meaning about the content of the video; rather it will be used as a static representation of the video file, which will be linked online after acceptance. Care should be taken to extract an image from the video which has reasonable clarity of fine lines and details. Acceptable file formats for still images are JPEG (.jpg) and GIF (.gif).
*Please note the below guidelines/considerations that apply to all multimedia submissions.
Authors will be asked to provide some information about their multimedia files. A caption or description of the content of the media file is required (similar to a typical figure caption). Additional metadata as outlined below will also be requested. This information is optional.
Metadata Elements:
- Caption/ description: Textual caption/description of the content of media object. Required.
- Type: The nature or genre of the content of the media, such as video or audio. Optional.
- Format: This should describe the media filetype, such as QuickTime, DV, MPEG, PCM, or WAV. Optional.
- Duration: This is the duration of the media object playing time, in units of seconds. It is applicable to video or audio media. Optional.
- Frame size: For video only (not still images), the size of the video image, as height × width in pixels. Optional.
- Producer: Information about the software used to create the media object. It should include the name and version of the software (e.g., Adobe Premiere Elements v. 2.0). Optional.
Multimedia Detailed Specifications
Acceptable Video File Formats:
- QuickTime nonstreaming (.qt or .mov)
- 24 bit (millions) color
- Video Compressor/Codec
- Uncompressed/None
- Animation
- Motion JPEG (MJPEG)
- DV—NTSC
- DV—PAL
- Audio
- 48,000 samples per second
- 16 bit
- Uncompressed/PCM
- Stereo or Mono
- MPEG
- Video Compressor/Codec
- MPEG2 (.mpg)
- MPEG4 (.mpg or .mp4)
- Video data rate 6 MB or greater
- Audio
- 48,000 samples per second
- 16 bit
- Uncompressed (PCM) or MPEG Audio at 224 KB or greater
- DV (.dv)
NTSC Video Parameters:
- Image size (H:V) 720:480 pixels
- Frame rate 29.97 frames per second
PAL Video Parameters:
- Image size (H:V) 720:576 pixels
- Frame rate 25 frames per second
Acceptable Audio File Formats:
- PCM, WAV, AIFF, MP3 (at 128 KB or greater)
- Audio Parameters
- 44,100 or 48,000 samples per second
- 16 bit
- Stereo or Mono
