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Does this book also explain NTSC and PAL formats? Or is that a different world?

dylan604 4y ago
Kind of hard to illustrate NTSC and PAL. These are the physical media. The tapes were not concerned with the types of signals that went on them. This is showcasing the physical nature of the video formats. If I were try to illustrate NTSC, the red would all be shifted to the right in the image in a blurry fasion. Not the hue itself shifted to the right, but the physical position of the red information ghosted to the right of the actual source in the image which would still be a shade of red, but most definitely, it wouldn't actually be red.
- TheOtherHobbes 4y ago
  NTSC was also known as "Never The Same Colour". NTSC and PAL were video encoding specs and also recording specs. The framerate and line resolution were part of the format, so PAL and NTSC recorders/tapes weren't compatible. For capture, PAL is basically 576 interlaced at 50Hz. NTSC is 480 interlaced at a little less than 60Hz. The physical line count is higher - 625 for PAL, 525 for NTSC - but these extra lines are either blank or used for supporting data. Most professional hardware could record/play either format, and a few systems could interconvert on the fly. But that took significant processing. The recordings themselves were one or the other. This carried through to video recorded on disk. Consumer analog video capture cards tended to be PAL or NTSC, sold by region.
  - taffronaut 4y ago
    From BBC Engineering in the 1970s: NTSC - "Never Twice the Same Colour" (US) SECAM - "System Exactly Contrary to the American Method" (France) PAL - "Perfection At Last" (UK - BBC of course)
    - dylan604 4y ago
      Most people don't realize that PAL came 10 years after NTSC. It also did not have to worry about maintaining backwards compatibility with the pre-existing black&white only format that was only a couple of years old. As much as I hate all of the pain that compatibility caused, it was an impressive feat of engineering. 30000/1001 was such a magic number that haunts me to this day.
      - tialaramex 4y ago
        > It also did not have to worry about maintaining backwards compatibility with the pre-existing black&white only format that was only a couple of years old. The BBC was broadcasting TV shows in black and white, and they were being received, in black and white, on people's black and white televisions for many years before PAL was developed. So yes of course compatibility was important, the existing sets continued to show (in black and white) newer colour shows, PAL is a method to encode colour on an existing black and white television signal just like NTSC. PAL isn't better because of somehow not worrying about backward compatibility, it's just a better technology.
ablwr 4y ago
It doesn't, it's a pretty simple book, intentionally. I had to remove a lot of more technical "fun facts" and replace them with something more historical / market-context-oriented so it would be fun for total novices (I had my mom tell me what was too confusing for her and swapped those out). I think one of the best books out there for really getting into video (algorithms, et al) is Charles Poynton's Digital Video and HDTV.

Kind of hard to illustrate NTSC and PAL. These are the physical media. The tapes were not concerned with the types of signals that went on them. This is showcasing the physical nature of the video formats. If I were try to illustrate NTSC, the red would all be shifted to the right in the image in a blurry fasion. Not the hue itself shifted to the right, but the physical position of the red information ghosted to the right of the actual source in the image which would still be a shade of red, but most definitely, it wouldn't actually be red.

TheOtherHobbes 4y ago
NTSC was also known as "Never The Same Colour". NTSC and PAL were video encoding specs and also recording specs. The framerate and line resolution were part of the format, so PAL and NTSC recorders/tapes weren't compatible. For capture, PAL is basically 576 interlaced at 50Hz. NTSC is 480 interlaced at a little less than 60Hz. The physical line count is higher - 625 for PAL, 525 for NTSC - but these extra lines are either blank or used for supporting data. Most professional hardware could record/play either format, and a few systems could interconvert on the fly. But that took significant processing. The recordings themselves were one or the other. This carried through to video recorded on disk. Consumer analog video capture cards tended to be PAL or NTSC, sold by region.
- taffronaut 4y ago
  From BBC Engineering in the 1970s: NTSC - "Never Twice the Same Colour" (US) SECAM - "System Exactly Contrary to the American Method" (France) PAL - "Perfection At Last" (UK - BBC of course)
  - dylan604 4y ago
    Most people don't realize that PAL came 10 years after NTSC. It also did not have to worry about maintaining backwards compatibility with the pre-existing black&white only format that was only a couple of years old. As much as I hate all of the pain that compatibility caused, it was an impressive feat of engineering. 30000/1001 was such a magic number that haunts me to this day.
    - tialaramex 4y ago
      > It also did not have to worry about maintaining backwards compatibility with the pre-existing black&white only format that was only a couple of years old. The BBC was broadcasting TV shows in black and white, and they were being received, in black and white, on people's black and white televisions for many years before PAL was developed. So yes of course compatibility was important, the existing sets continued to show (in black and white) newer colour shows, PAL is a method to encode colour on an existing black and white television signal just like NTSC. PAL isn't better because of somehow not worrying about backward compatibility, it's just a better technology.

ablwr 4y ago

It doesn't, it's a pretty simple book, intentionally. I had to remove a lot of more technical "fun facts" and replace them with something more historical / market-context-oriented so it would be fun for total novices (I had my mom tell me what was too confusing for her and swapped those out). I think one of the best books out there for really getting into video (algorithms, et al) is Charles Poynton's Digital Video and HDTV.