Video Preparation

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This article defines the formats for uploading to the platform. If you are looking for references to which formats the player will play back, please see Supported video and audio formats reference

JWX automatically transcodes video files that you upload to our dashboard. (Experimental codecs are not supported.) The file must have a duration of at least 2 seconds. If you are uploading video files to the dashboard, there is a 100GB file size limit.

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100GB upload size is available only with v2 Uploads entitlement. The file size for v1 is 25GB. To upgrade to v2 entitlement, contact your JWX representative.

Please note that if you are uploading content via the JWX Management API, the file size limit may differ. For more information, learn how to upload content via the API.

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Video Format

You can upload most media asset formats to your JWX account. The following is a list of media asset formats that are commonly uploaded to JWX:

• .3gp
• .avi
• .mov
• .mp4
• .wmv

Although the JW Platform accepts the above-listed media asset formats for upload, it then transcodes them into .mp4 and HLS formats. JWX does not retain the uploaded media asset formats in the player for output.

However, the 3GP media asset format is the notable exception as it is, essentially, interchangeable with the mp4 format on most devices. 3GP was designed for older devices unable to play MP4. For best compatibility, 3GP usually only utilizes the H.263 video codec instead of the H.264.

Files encrypted with Widevine, PlayReady, or Fairplay DRM cannot be uploaded to your JWX account. However, you can enable content protection for files after they are uploaded. You can also play DRM-encrypted media in a JWX player.

If you control the output format (for example, when exporting the video from your editor), we recommend uploading your videos using one of the following formats:

• MP4 container format
• H.264 video codec
• AAC audio codec

MP4 with H.264 video and AAC audio is a widely supported, industry-standard format. Most modern editing, compositing, screencasting, and transcoding tools can export to it. If your tools do not support this format, consider using Handbrake, a free and powerful desktop transcoder.

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Dimensions and Bitrates

In terms of dimensions, bigger is better. Video in 720p is today's standard. We also see an increase in 1080p uploads. If your original video is full HD, we suggest you upload 1080p too. If your source footage is standard definition (NTSC, PAL), we suggest using 360p. Anything smaller than 360p is not recommended.

Since H.264 and AAC are highly efficient codecs, high upload bitrates are not necessary. However, the bitrate should be high enough to avoid quality loss. The JW Platform creates the final streaming encodes, so if the source file already contains compression artifacts, they may be amplified in the final transcodes and result in poor playback quality.

The table below includes recommended format, dimensions, audio, and video bitrates. If you upload videos in these formats, the JW Platform will be able to build high quality transcodes and deliver smooth playback across devices.

Note that our built-in transcoding will generate smaller versions of your uploaded video. If you upload content in 1080p, only viewers whose devices and connections support 1080p playback will see that resolution. Other viewers on older computers or phones will see lower resolution transcodes (such as 360p or 180p).

Keep in mind that if your upload contains 5.1 audio tracks, we will retain the 5.1 audio for 720p, 1080p and higher. At lower resolutions, the 5.1 audio will be down-mixed to stereo. This provides a better playback experience for your audiences on networks where bandwidth is limited.

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It is highly recommended that you prepare your uploads using a constant, non-fractional frame rate. This will avoid timing issues and other glitches during transcoding. For example, instead of encoding your videos at a variable 29.97 frames-per-second (fps), use a constant 30 fps.

Additional Settings

There are many more settings associated with video encoding. Here are some additional suggestions to follow when exporting your video for upload:

• Use progressive frames (e.g. 720p) instead of interlacing (e.g. 720i). Interlacing does not apply to online video and JW Platform will introduce artifacts when attempting to filter it away.
• Use a screen aspect ratio of 16:9. This will fill the screen of many monitors, laptops, tablets and phones with your footage. More rectangular (4:3) or cinematic (2.39:1) ratios will result in black borders on many screens.
• Use a pixel aspect ratio of 1:1. Older broadcast formats (like PAL or NTSC) use non-square pixels, but online video pixels are always square. JW Platform may have troubles converting non-square pixel aspect ratios, resulting in a stretched image.
• Export the to-be-uploaded videos in MP4 format and not in MOV. The latter contains additional features like Edit Lists that often result in audio-video sync issues.
• If available, select the Main or High profile for the H.264 video. These profiles support features like B-frames and CABAC, resulting in higher quality at the same bitrate.