It is possible for pixel information to change due to the compression or supported color depth of the format you are converting/saving to.
It depends on the format and compression.
The video coding format MPEG is used through the web for video compression. MPEG goes up to MPEG- Part4 that is shortened to MP4.
MP3
DVD format is not supported by YouTube. So you have to convert DVD to YouTube supported format. WebM video format is supported by YouTube and also this format is very adapted for on video sharing site and provides good video quality and smaller file size. You can refer to the related links for the guide to convert DVD to WebM and then uploading to YouTube.
3gp
It is: 23,700,000,000
i need software
2
If your song file is not supported, it might be a good idea to convert it into a format that is supported. There are several online resources that can help you convert your file for free.
Compression methods are used for images compression and most common compressions are JPEG which is lossy (you can lost some details or quality of image), LZW which is lossless, RLE and ZIP also lossless compressions.
Right click the file and choose get info. If that doesn't solve the problem it's either due to a file permission problem or a file format problem. Check if your user is the owner of the file and if the file format is supported by iTunes. If not you will have to convert it to a supported format.