Proof of Media — hashing reporters’ content on Reporter

Many have asked us about how blockchain hashing works in the case of Reporter. How does a blockchain based media solution work?

In simple terms, hashing means taking an input string of any length and giving out an output of a fixed length. The hash output can be used for data lookup, indexing or even verification purposes.

In the context of Reporter Community’s solution, the ID of the media content —as recorded by the Reporter app — the metadata, and some smartphone sensor data are taken as an input.

1. Reporter media content ID

The Reporter app is assigning a unique ID to each media content (photo or video) by using the following structure:

1AA111A1–1AA1–11AA-A11A-111A11AA1A11
(where the 1 means a number, the A means an alphabetic character)

2. Media Content’s Metadata

Metadata is a set of data that describes and gives information about other data. A content’s metadata allows information to be transported with an image file, in a way that can be understood by other software, hardware, and end users, regardless of the format. Metadata is information entered into the image file by users, or by automated capture from cameras or scanners. It is stored in two main places:

• Internally — embedded in the image file, in formats such as JPEG or TIFF.
• Externally — outside the image file in a digital asset management system (DAM) or in an auxiliary file, such as XMP, or an external XML-based news exchange format file as specified by the IPTC.

There are 3 main categories of data:

• Administrative — identification of the creator, creation date and location, contact information for licensors of the image, and other technical details;
• Descriptive — information about the visual content, including headline, title, captions and keywords through free text entry or by inserting codes from a controlled vocabulary;
• Rights — copyright information and underlying rights in the visual content including model and property rights, and licensing terms.

It’s important that the metadata stored in an image file stays with the image. Metadata is essential for identification and copyright protection. Metadata are also key to smoothing workflow, easily finding digital images via search — online or offline — and tracking image usage.

From the complete metadata structure, we think the following data is needs to be stored on the blockchain for unique content:

3. Smartphone sensor data

Smartphone sensor data provides additional information about the surroundings and conditions of the content’s creating. We will use the following necessary to create the hash output stored on the blockchain for each content:

• Accelerometer — axis-based motion data with a srtucture of 1111;
• Gyroscope —complements accelerometer data with phone’s orientation;
• Magnetometer — the electronic compass measuring magnetic fields and providing information about position compared to cardinal North;
• Pressure sensor — a barometer that measures air pressure;
• GPS — providing geolocation data;
• Light sensor — supplying ambient light condition data;
• Cell information — data on location compared to cell phone towers;
• and finally — time.

Based on these categories of data the app runs a hashing algorithm, providing an output of a fixed length.

Regardless of the length if the input, the output will always have a fixed length. The process shouldn’t be critical, as we are not dealing with a huge amount of data (we will store the 3 input data categories and the media content on the Amazon AWS, or an affordable similar blockchain based storage solution).

In essence, Reporter’s proof of media solution will create a portfolio of authenticated, verifiable digital content pool. Support out token sale to make this happen fast, you find more information on our website or chat with us on our Telegram channel.