![]() ![]() Why can we only shoot 400 Mbps internally? If you need more, you need to attach an external recorder and record Prores HQ, which has a maximum data rate of 880 Mbps. However, the GH5 will only have a 400 Mbps option internally. This is the data rate the GH5 needs in 10-bit 4:2:2 just to be better than 100 Mbps 8-bit 4:2:0. Necessary data rate: 280 Mbps x 2 = 560 Mbps But the 400 Mbps option will arrive as an intraframe codec. The traditional way has been to equate interframe and intraframe in this way:ĥ0 Mbps interframe = 100 Mbps intraframe (for 1080p)Ģ00 Mbps interframe = 400 Mbps intraframe (for 4K)Īs we saw above, 10-bit 4:2:2 should have a data rate of 280 Mbps in interframe. Read this first: Choosing a broadcast camera For an intraframe codec, the number is double that. So, the data rate for 10-bit 4:2:2 should be at least: To really maintain the difference, 10-bit will have to compressed by: ![]() What you’ll see is that even though 10-bit needs 1.67 times more data, it is more heavily compressed, and therefore is only bigger by: How much compression is this? Here’s the math:Ĩ-bit 4:2:0 – From 2438 Mbps to 100 Mbps is 24 times!ġ0-bit 4:2:2 – From 4070 to 150 Mbps is 27 times! Later in 2017 we’ll have the 400 Mbps option. ![]() The Panasonic GH5 gives you 8-bit 4:2:0 at 100 Mbps and 10-bit 4:2:2 at 150 Mbps internally. Step Two: What you get with the Panasonic GH5 So, you can see that 10-bit needs about 1.67 times the space as 8-bit to be different: In this case let’s assume the frame rate is 24 fps:Ĩ-bit size: 12.7 MB x 24 fps = 305 MB/s or 2438 Mbpsġ0-bit size: 21.2 MB x 24 fps = 509 MB/s or 4070 Mbps The next step is to get the data rate by multiplying by the frame rate:ĭata rate = Size of one frame x number of frames per second Also remember, there’s always a small overhead for file and metadata information, but it’s negligible for calculation purposes. We are dividing by (8 x 1024 x 1024) to convert bits to Megabytes. Don’t be Confused between RGB 444 and Y’CbCr 444Īs mentioned in the article above, to find the uncompressed file size of one frame, use this formula:Ĭhannels x Bit Depth x Chroma Subsampling Percentage x Resolution. ![]() What’s the difference between YUV, YIQ, YPbPr and YCbCr?.To learn more about this read the following articles: Once it is, it will also have three channels.Īs a separate note, YUV footage also has three channels, one for luminance and two for chrominance. If you’re shooting RAW, there’s only one channel, because RAW hasn’t been debayered yet. That’s why we have to multiply the data by 3. I’m assuming you’ve read the articles above, because these calculations follow everything I’ve laid out earlier.Ī full color image (produced by a camera) is a raster image and has three channels – Red, Green and Blue. Bits vs Bytes, and the story behind Disk Drive Sizes.What’s Stopping us from having a Universal Codec that will Benefit Humanity?.What is inteframe and intraframe compression?.What is color bit depth, color space, color model, CIE, luminance and chrominance, and chroma subsampling?.The Difference between Lossy and Lossless Compression.Here are some preliminary articles that explain the terminology, formulas, etc., mentioned in the video: The video references a few articles I’ve written earlier and some calculations that will help you follow my arguments. For 10-bit 4:2:2, shoot 880 Mbps Prores HQ externally.For 10-bit 4:2:2, shoot 400 Mbps internally, or.The Panasonic GH5 Guide is now available! Click here to learn how to make cinematic videos with the Panasonic GH5. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |