2017-05-17, 12:11 AM
Once upon a time, there were analog formats... VHS, Laserdisc, VHD, CED - all "stuck" to their beloved video system, PAL and NTSC; not "fixed" resolution, apart 525 (485 visible) horizontal lines for NTSC, and 625 (575 visible) horizontal lines for PAL, or vertical resolution... horizontal resolution was "supposed" by the signal in MHz - 1MHz = 80 vertical lines, or horizontal resolution.
Then digital video appeared in the market; first primitive CD-I (then evolved quickly to VCD) with its "astounding" resolution of 320x240 (NTSC) and 320x288 (PAL) pixels, for a "whopping" sub 0.1Mpixel image!
VCD evolved into what we all know, DVD, with its max resolution set at 720x480 (NTSC) and 720x576 (PAL).
Then DivX (not "that" DIVX!) surface, and every strange resolution combination came up...
HDTV set a standard to 1280x720 and 1920x1080 as the most used resolutions; sometimes we see that horizontal resolution in video files is the same, but the vertical change, accordingly to the aspect ratio. And I can understand it, somehow. Let's say, we were in the "video Far West" with all those resolutions, and now I thought to have reached a "compromise" somehow: horizontal basic resolutions of 720 (SD), 1280 (HD), 1920 (FHD), 3840 (UHD), and eventual vertical adaptation following aspect ratio.
But no, it was too simple... I can undestand (somehow, but don't like it) that a non-studio made video file could use different resolutions, but I'm asking myself why properly released files on the net - streaming and download - adopt such strange, out of standard resolutions? I mean, I can even allow a, let's say, 960x540 resolution, as it's 1/4th of FHD (as 640x360 1/4th of HD), but, would we talk about the following ones (taken just for example)?
iTunes - The X-Files "Pilot" s01e01
1452x818 (stated as 1080p, and it is NOT) - AR 1.78:1 (more or less)
iTunes - Harry Potter and the Half-Blood Prince
1848x800 (stated as 1080p, and it's OK) - AR 2.30:1 (when OAR is 2.40:1)
iTunes - Harry Potter and the Chamber of Secrets
1918x800 (1080p, OK) - AR 2.40:1 (WHY "shave" 2 pixels horizontally?!?)
RaiPlay (Italian, streams films and other video originally broadcasted on various Rai channels)
928 x 522 (?!?) - AR 1.78:1 (more or less)
add insult to injury, resizing these odd resolutions would result in a worst quality than let's say, 1280x720 or 960x540.
Any idea?
Then digital video appeared in the market; first primitive CD-I (then evolved quickly to VCD) with its "astounding" resolution of 320x240 (NTSC) and 320x288 (PAL) pixels, for a "whopping" sub 0.1Mpixel image!
VCD evolved into what we all know, DVD, with its max resolution set at 720x480 (NTSC) and 720x576 (PAL).
Then DivX (not "that" DIVX!) surface, and every strange resolution combination came up...
HDTV set a standard to 1280x720 and 1920x1080 as the most used resolutions; sometimes we see that horizontal resolution in video files is the same, but the vertical change, accordingly to the aspect ratio. And I can understand it, somehow. Let's say, we were in the "video Far West" with all those resolutions, and now I thought to have reached a "compromise" somehow: horizontal basic resolutions of 720 (SD), 1280 (HD), 1920 (FHD), 3840 (UHD), and eventual vertical adaptation following aspect ratio.
But no, it was too simple... I can undestand (somehow, but don't like it) that a non-studio made video file could use different resolutions, but I'm asking myself why properly released files on the net - streaming and download - adopt such strange, out of standard resolutions? I mean, I can even allow a, let's say, 960x540 resolution, as it's 1/4th of FHD (as 640x360 1/4th of HD), but, would we talk about the following ones (taken just for example)?
iTunes - The X-Files "Pilot" s01e01
1452x818 (stated as 1080p, and it is NOT) - AR 1.78:1 (more or less)
iTunes - Harry Potter and the Half-Blood Prince
1848x800 (stated as 1080p, and it's OK) - AR 2.30:1 (when OAR is 2.40:1)
iTunes - Harry Potter and the Chamber of Secrets
1918x800 (1080p, OK) - AR 2.40:1 (WHY "shave" 2 pixels horizontally?!?)
RaiPlay (Italian, streams films and other video originally broadcasted on various Rai channels)
928 x 522 (?!?) - AR 1.78:1 (more or less)
add insult to injury, resizing these odd resolutions would result in a worst quality than let's say, 1280x720 or 960x540.
Any idea?