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I've seen this post about what exactly "RAW" is.
My question is about the GoPro Hero 4, which comes with the Protune option for "advanced controls".
In their description, GoPro uses the term "less compression", but I was under the impression that RAW meant NO compression at all.
Camera raw sounds like it is effectively similar to RAW because it is describing the light data without any corrections. What comes in on the sensor is written out, but it does sound like it may be applying the filter, just using a mix of 1:1:1 for the color resolution. It's theoretically possible to work backwards from this to the full colors, but you may lose some bit depth if it goes from more than 8 bit sensor read out to 8 bit color encoding. Possibly even worse if it is encoding to 4:2:0 or 4:2:2.
The net effect of shifting color on this kind of a recording would be that there would be fewer total colors described after applying your corrections since you discard a portion of the possible colors that could be described by the format. (Where as your more traditional RAW doesn't discard any data, so you can be more selective about what you want to remove when you reduce the bit depth later in the process.)
I believe the GoPro Hero 4 records in the h.264 format which is contained inside the MP4 Format. This codec is a Compression format and dependant on the recording bitrates.
h.264 is a universally accepted format that Allows for very large files to be compressed with minimal loss to the original content. The compression is dependant on the bitrate used; the higher the bitrate, the larger the file, and the lower the bit rate, the smaller the file. Satellite TV channels, although 1080p @24 FPS, are of a fairly low bitrate as they need to fit the bandwidth available. However, even then, sometimes images come across as blocky.
A Raw Image at full Bitrate will definitely be larger than the MP4 Image and taking into consideration, you can't have a video camera that can only take a few minutes of Film, the bitrate needs to be reduced to allow for longer footage.
If the Hero 4 is as good as the Hero 3, the loss of quality will not be something that will be noticeable and as good as if no compression had taken place.
Regarding editing, h.264/MP4 is pretty much the choice of all editing packages now. You may be required to install the latest version of Quicktime to ensure you have the latest codecs.
