The result might be that you see elements of the image that weren’t visible (or prominent) when you captured it.įor example here is an image that was captured raw. If you are doing any sort of color correction, then you will be changing the image. You should care because you may want to change the image. If the image looks just as good to my eye, then why should I care if it’s technically ‘lossy’? Using a more lossy codec can be a really smart move because of how much space it saves. In some cases (when viewing online, for instance), it’s really not necessary to retain 100% of the original image. A more lossy codec is not necessarily bad. The lossyness is a combination of the techniques that the particular codec uses and its bitrate. And if they’re pretty different, then it’s more lossy. The question is: If I had an uncompressed image, and then I compressed it with this codec, how similar would the new image be to the old image? How much information is lost in the transcode? If the two images are very similar, then the codec is not very lossy. I mean the amount of data that is retained by the codec, only some of which you can see. When I’m talking about lossyness, I don’t necessarily mean what your eye sees. One of the columns in the table is “lossyness,” which is an important concept with codecs. That way you can compare codecs as you read through the article. And it’s easier to find help if something goes wrong. They are more likely to work on your system, your client’s system, your system-in-five-years, etc. There is a significant advantage to using popular codecs. The ones I’ve included are by far the most common. There are many different codecs that can be used in the editing process. This list can help you compare different codecs against each other and make the best decision for your project. I’ve also pulled together a list of all of the most common codecs used in the postproduction world. Deeper bit-depth (larger numbers) is good for color-correction and VFX. Bit depth: The number of possible colors.Temporal compression: Uses previous frames (and sometimes following frames) to calculate the current frame.Almost all codecs use this to some degree, and the amount tends to vary with the bitrate. Macro-Blocking: Finds blocks (varying size) of similar colors and makes them all the same color.Really bad if you’re doing green screen or VFX work.
4:2:2 is some chroma subsampling.4:2:0 is lots of chroma subsampling).
If you’re skipping the video, here are some very basic explanations: It’s not required viewing to understand this article, but it certainly won’t hurt. A few years ago, I created a video that covers the main compression techniques that many codecs use. And they’re pretty smart about how they do that. What a Codec DoesĪ codec is a method for making video files smaller, usually by carefully throwing away data that we probably don’t really need. You’ll be able to work faster on a laptop than many can on a high-end tower. It can also make your work faster, and lets you take the best advantage of your computer and storage. Choose the right codec and you’ll preserve your images in the highest quality. The benefits of optimizing your codecs can be huge. I’ll also give you some examples of the most commonly-used codecs for that stage.Īlong the way, we’ll cover why low-end codecs and high-end codecs can each slow down your editing, the reasons for a proxy/offline edit, a real-world project walkthrough, some storage-saving strategies, and an explanation for why transcoding cannot improve your image quality. I’ll cover:Īt each stage, I’ll explain which factors you should be considering as you choose a codec. Click on a heading to jump to that section. I’m going to walk you through every step in the process of making a video. So you can choose the right codec for yourself, instead of relying on what worked for someone else.
My goal is to give you what you need to make your own informed decisions about codecs.
By the end of this article, you will be able to pick the best codec for you on each project.