Youtube has also enabled mobile uploads using the 3gp format
When YouTube was initially launched, it was possible upload long videos. However, the team at YouTube found that the long videos had copyrighted content and unauthorized TV programs, serials, and movies. Hence, in March 2006, an upper limit of ten minutes was introduced. This limit increased to 15 minutes in the year 2010, and today all users can upload videos up to 15 minutes. YouTube has a feature wherein those users who comply with the Community Guidelines can upload videos of up to 12 hours. This requires account verification along with a cell phone. Videos on YouTube can be uploaded in various formats and almost all formats are accepted by YouTube including .MOV, .DivX, .OGG, .AVI, .MKV, .OGY, .VOB, .MPEG, .WMV, .MP4, and .MPEG-4. YouTube has also enabled mobile uploads using the 3GP format. The video formats use progressive scanning and are only then uploaded on YouTube. Those with interlaced scanning are required to be changed into a progressive scanning format as it reduces the clarity of the video.
Quality and Formats
When it first came out, YouTube offered all its videos only with the mono MP3 audio and used the Sorenson Spark codec. This was similar to H.263, and the videos had a resolution of 320×240pixels. This was extended to a higher resolution of 480×360 pixels in 2008. YouTube also offered the option of watching videos on phones using the 3GP format. It has progressively increased the amount of resolution for watching videos; for instance, in the year 2008, videos could be streamed at a resolution of 720 pixels in high definition. During this time, the player size was increased to a ratio of 16:9 widescreen as opposed to the previous 4:3 aspect. YouTube also changed its default video compressing format to H.264/MPEG-4 AVC. The next year, that is, 2009, it supported 1080 pixel worth of resolution in high definition. In 2010, the 4K format was introduced, which supported videos with a resolution of up to 4096×3072 pixels. In 2015, YouTube increased its support base to 8K-resolution format, and videos could be played at 7680×4320 pixels. Videos are also offered in various qualities including standard quality (SQ), high quality (HQ), and high definition (HD). These are represented by the resolution and pixels.