Transferring Video

Uploading and Downloading Video

Video can be uploaded from a camera or from a computer to a remote system in order to allow someone in another location to view or download the video. The remote system could be one that you own and control, owned by an entity that you pay a subscription fee to use (e.g. Amazon, Dropbox), or owned by an entity that lets you upload for free (e.g. YouTube, Internet Archive).

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Transferring Video Files

No matter how or where you upload and download, transfer video files in a way that preserves their authenticity and usability:

Transfer the original file

For raw video footage, the original file is the most authentic and highest quality copy of your video, and contains valuable embedded metadata. Upload your original files to a location that will maintain their integrity and that will allow you to download without altering or transcoding the files. Always download original files if they are available.

Download original files if they are available.

Alternatives to the original file

If it is not possible to download the original file (e.g. if you are downloading from YouTube), obtain the highest quality copy available in a current and widely used format. Note that important embedded metadata (e.g. date and time recorded) can be lost in transcoded copies, so document and upload important metadata in a separate form (e.g. in your YouTube title and description).

Some metadata may be lost if you download transcoded files.

Try This: ADVANCED

YouTube Data API allows you to access some metadata from your original file that is not present in copies downloaded from YouTube, which are transcoded.

Check your transfer

Transfers can be interrupted, so check your files to make sure they have transferred completely and intact. A simple way to check is to see that the file sizes and number of files match, and to play a sampling of the videos. If hash values are available for the files, verify against the hashes. See the section on “Keeping Files Intact (and Proving It)” for more on how to do this.

Choosing a System/Service for Sharing Files

Whether you own and control your own remote server, or use a free online file sharing service to transfer your videos to others, there are a few key factors to keep in mind:

Permanence

Since you may need to download the file at some point after you have uploaded it, the system should not remove or delete your videos without your authorization, or at least without adequate advance notice.

Data integrity

The system should enable you to download an exact copy of what you uploaded, without alteration, data loss, or corruption.

Security

The system should not be vulnerable to unauthorized access. In cases where you have restricted information, choose a system that allows you to encrypt or limit access to selected files.

Custody

The system should monitor and log activities that affect the video (e.g. who uploaded and when, who accessed and when, who edited and when, etc).

Documentation

If you have accompanying documentation, like consent forms or shotlists, choose a system that allows you to keep this documentation associated with the video.

Accessibility

The system should enable you to access and download your videos in the manner and at the frequency you need.

Efficiency

The system’s method for uploading and downloading needs to to suit your time and resources.

Cost

You must be able to afford the system’s cost to upload and download videos in the volume and frequency that you need.

Comparison of Popular Systems/Services

File sharing services all handle uploaded files differently, potentially affecting their authenticity, integrity, and usability. This downloadable tipsheet compares a few popular commercial services, while this tipsheet focuses on security-minded transfer tools.

Be aware that technologies and terms of use change frequently, so check for the most current information before making a decision.

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Upload

To send data from a local computer system to a remote one. The inverse of upload is “download.”

Download

To receive data from a remote computer system and save it in a local computer system. The inverse of download is “upload.”

Authenticity

The quality of being genuine, not fake or counterfeit, and free from tampering. Authenticity means that an object was actually created by the person represented as its creator, and that it was actually created at the time and place that is represented as its time and place of creation. Video footage that has been manipulated or altered but is represented as if it had not been, for example, is not authentic.

To authenticate a video means to verify the relationship between it and its creator and point of creation. Documentation about who created something, when and where it was created, and the chain of custody can provide a starting point for this authentication process.

Original File

In the digital realm, the “original file” is any copy of a file that is exactly the same (i.e. bit-for-bit) as the file in question when it was created. This means that there are no accidental or deliberate alterations to any aspect of the file, including its format and technical specifications.

Embedded Metadata

Metadata that is stored within the digital object it describes. Some embedded metadata, such as file size, are essential to the functioning of the file, and are always written to the file by the device or software system. Other embedded metadata are non-essential and can be optionally added (e.g. rights information). Embedded metadata is not guaranteed to be accurate—for example, if your camera is set to the wrong date. Embedded metadata stay with the digital object as long as the object is intact, but can be intentionally stripped or altered. Embedded metadata can be lost if a file is transcoded to another format.

Integrity

The quality of being whole, unaltered, and uncorrupted. A file that is not intact may not be usable or may have decreased informational and evidential value. Videos files can lose their integrity if they are accidentally mishandled, deliberately tampered with, or if data corruption occurs in transfer or storage due to hardware or software malfunction. The best way to ensure integrity is to establish a system to check file fixity regularly (e.g. by computing hashes and checking them against a registry of previously computed hashes) and to restore any corrupted files from an intact copy.

Transcode

To re-encode a digital file to a different encoding scheme, such as converting an H.264/MPEG-4 AVC video to Apple ProRes. Transcoding is usually done when a video’s encoding is not supported by the system that needs to use it. Transcoding fundamentally alters the file, although lossless methods can allow the original data to be reconstructed from the transcoded data.

Hash Value

The string of alphanumeric characters that results from running a hash function algorithm on data or a file. The hash value of a file will always remain the same as long as the file is unchanged, so it can be used to identify altered, corrupted, and duplicated files.

Encryption

The process of encoding your files using a cryptographic algorithm so that only authorized parties with a “key” (e.g. a password) can decrypt them. The two main types of encryption are symmetric-key and public-key. Symmetric-key encryption uses the same key, or password, to encrypt and decrypt information. Public-key encryption uses one key to encrypt, and a different one to decrypt, and is more secure.

Metadata

Any information about a video: from technical information embedded in the file that allows the video to function, such as format and duration, to descriptive information about the content to help you understand or find it–such as keywords, security restrictions, geographic locations, and so on. Metadata is critical to any future use, and is important throughout the archiving process.

Despite what is sometimes said, images almost never speak for themselves. They require context and description to make sense, to corroborate their factuality, and to be accessible beyond one person’s memory or desktop.

Metadata can be automatically generated and embedded in the file, such as with technical metadata, or it can be manually recorded on an external medium, such as with descriptions, security flags, and keywords in a database. Metadata capture sometimes needs to be manually enabled on your device, such as with GPS or location services.

Offload

To copy media from a camera or memory card to a storage device connected to a computer.

Chain of Custody

Chronological documentation that shows who has held or controlled a video file from the moment it was created. The ability to show an unbroken chain of custody is one important indicator of the authenticity of a video, and therefore a factor in using video as evidence.

Information Package

A self-describing container — usually a clearly named folder or directory — used to keep media and its related documentation or metadata together.

In This Section

Introduction
Offloading from Cameras
Uploading and Downloading Video
Keeping Files Intact (and Proving It)
Physical Transport
Transferring Videos and Metadata Together

Takeaways

When offloading videos from your camera to your computer, make sure you transfer the files completely and without alteration.
Always make sure to include your metadata and documentation with your video—or make sure they can be matched together after transfer.
If using the Internet to transfer files, choose a file sharing service that meets your needs for permanence, data integrity, security, chain of custody, documentation, accessibility, efficiency, and cost.
Use hashes to check that your files have transferred intact, and to show that your files have not been altered over time.
If physically transporting drives, make sure to have another copy and be aware of cross-platform constraints.
Organize your videos in “information packages,” or folders with your video and metadata, for transfer.