However RAW video codecs record the complete sensor data. With regular video formats, debayering happens in-camera, before the video file is recorded to your media. The process of converting the sensor data into a viewable video image is known as debayering or demosaicing. However, camera sensors are comprised of image capturing photosites which only capture a single primary color. The color of each pixel is determined by three primary color values (red, green and blue). The graph above shows how small the file sizes are for ProRes when compared to uncompressed video. Graph comparing the data rates of the different ProRes formats to uncompressed video (source: Apple ProRes White Paper) Still delivers full-resolution video but is even more highly compressed with a target data rate of 45 Mbps. This version of the codec has 70% of the data rate of ProRes 422 and 30% smaller file sizes. As a result, ProRes 422 offers even better real-time editing performance. Offers nearly all the benefits of ProRes 422 HQ but at only 66% of the data rate. The codec will remain visually lossless even after multiple generations of decoding and re-encoding during post-production. This version of ProRes gives the same high level of image quality as ProRes 4444 but for 4:2:2 image sources. ProRes 4444Īn extremely high-quality format, again for 4:4:4:4 video with an alpha channel. The codec supports up to 12 bits RGB channel and a 16-bit alpha channel. It includes an alpha channel for visual effects work. The highest-quality version of ProRes for 4:4:4:4 video sources. The target data rates given are all for 1920 x 1080 video at 29.97 fps. For an explanation of the terms 4:4:4:4, 4:2:2 and chroma sampling please read the Videomaker article The Anatomy of Chroma Subsampling The codec offers a range of different formats with different data rates and corresponding file sizes. ProRes files will appear on your computer as. To understand bit depth in more detail, read the Videomaker article Understanding Bit-depth and Color Rendition for Video ProRes formats This reduces color banding in areas of gradation in tone, such as a blue sky. ProRes is also a 10-bit codec which means that it can display 4 times the range of colors and shades when compared to an 8-bit file format. Compression is applied to the data within each frame to reduce the overall data rate. It is an intra-frame codec which means that every frame is saved. ProRes was created to enable high-quality, high-performance editing in Final Cut Pro. However inter-frame codecs are less suited to editing, where the need to be able to cut on every frame is important. For the intervening frames, only the differences from the complete frames are saved. Inter-frame encoding reduces the data rate by saving a small number of complete video frames. For more information on codecs check out the Videomaker guide What is a CODECĪt the time, the high data rate required by HD video meant that file formats used inter-frame compression. The term codec simply comes from the shortening of two words: coder and decoder (co/dec). ProRes is a video file format, or “codec”, developed by Apple in 2007. This guide to ProRes and ProRes RAW will explain how the file formats work, the benefits they offer and when best to use them. If you aren’t sure what any of that means, don’t worry. ProRes RAW is the relatively new kid on the block and adds the power of RAW video to the benefits of the ProRes codec. It combines extremely high image quality with small file sizes for efficient playback. ProRes is one of the most well-known and widely used video file formats.
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