VideoHelp Forum
+ Reply to Thread
Results 1 to 9 of 9
Thread
  1. Member godai's Avatar
    Join Date
    Oct 2012
    Location
    United States Florida
    Search PM
    hi any good switcher hdmi 5x1? i have one kinovo but im getting a less sharper image and darker in my case just like component one, i compare plugging directly hdmi cable to tv and with this switcher, but alsow i have one hdmi 5 in one out and signal its like one directly,

    any advice?

    also if it can strip hdcp can be great. thank you.
    Quote Quote  
  2. Originally Posted by godai View Post
    hi any good switcher hdmi 5x1? i have one kinovo but im getting a less sharper image and darker in my case just like component one, i compare plugging directly hdmi cable to tv and with this switcher, but alsow i have one hdmi 5 in one out and signal its like one directly
    If your switcher is analog one (then it is not HDMI) then "less sharper image and darker" is possible, if you have true HDMI switcher then it is not possible - HDMI is digital video and until digital signal is not degraded to point where you get nothing except noise then you receive perfect signal. Now way to make picture less sharper as this imply real time digital filtering of high speed data (many GB per second) - something not cheap in terms of resources.
    Modern HDMI switchers not even participate in HDCP decryption like first generation of HDMI switches, they may only perform some limited equalization of digital signal to improve SNR and reduce jitter. So unless there is serious malfunction in your setup then you can't claim "less sharper and darker" image as it is against foundation of HDMI interface. It is only feasible if your HDMI resolution drop due issues with EDID so your source get or wrong or not at all EDID data and fall back to SD resolution.
    Quote Quote  
  3. Member
    Join Date
    Jul 2007
    Location
    United States
    Search Comp PM
    I have a couple of low cost HDMI splitters that if the cables are not firmly inserted, show a picture with a heavy green cast, sometimes on one output, sometimes on two. The full detail of the picture is there, just with a green cast. I didn't think it was possible since digital is digital, but there's something happening that with the boxes.
    Quote Quote  
  4. Member godai's Avatar
    Join Date
    Oct 2012
    Location
    United States Florida
    Search PM
    well its 100% switcher its hdmi, and looks some darker and less sharper and if i connect directly to my tv looks better. also i get sharper image with couple splitters.
    Last edited by godai; 4th Jun 2018 at 08:53.
    Quote Quote  
  5. Originally Posted by lingyi View Post
    I have a couple of low cost HDMI splitters that if the cables are not firmly inserted, show a picture with a heavy green cast, sometimes on one output, sometimes on two. The full detail of the picture is there, just with a green cast. I didn't think it was possible since digital is digital, but there's something happening that with the boxes.
    Green cast may imply channel issue - can happen - sometimes EDID is to be blamed sometimes internal design of HDMI receiver but still sharpness will be same as in source - sharpness loss is not possible until HDMI data are decoded and processed. Distortions that will affecting HDMI are mostly related to clocking (phase accuracy) and they can be measured (so called eye pattern).
    To describe this in different way - if i read about softened image and/or subtle tonal differences then it is like someone describing SATA HDD that store your files and everything is fine (folder structure, no errors on filesystem) however your excel or word documents have all capitals changed to lowercase...

    Eye pattern looks like this and sane HDMI switch may improve digital data levels and apply re-clocking and some equalization to deal with long cables loss but it is unable to modify data especially in intelligent way (so keep image structure but alter sharpness) especially when data are HDCP protected (they are scrambled so video looks like colour RGB/YCbCr noise):
    Click image for larger version

Name:	1227_1.jpg
Views:	424
Size:	754.2 KB
ID:	45828
    Another example of eye pattern diagram:
    Click image for larger version

Name:	eye-diagram.png
Views:	378
Size:	179.8 KB
ID:	45829

    HDMI switcher see HDMI data only as series of 0 and 1 and it is able only to alter signal level and sometimes improve timing of those 0 and 1 - usually HDMI receivers are more tolerant than absolute minimum required by HDMI standard so that's why we may have 20 meters long HDMI cables even if standard specify only maximum 5 meter, better cable with better HDMI receiver will be able to work without problem but this is extreme case.

    Originally Posted by godai View Post
    well its 100% switcher its hdmi, and looks some darker and less sharper and if i connect directly to my tv looks better. also i get sharper image with couple splitters.
    It is not possible by way how HDMI is designed - it may be possible if your HDMI source switching to lower resolution (for example EDID line is corrupted and HDMI signal flow from HDMI source to HDMI sink falling to some minimum common video mode like 720x480).
    Quote Quote  
  6. Member godai's Avatar
    Join Date
    Oct 2012
    Location
    United States Florida
    Search PM
    what i can say to you? i don't know about technical aspects, just with my eyes. and its clear that happen hdmi switcher its offering me less quality signal. sorry about that.
    Quote Quote  
  7. Originally Posted by godai View Post
    what i can say to you? i don't know about technical aspects, just with my eyes. and its clear that happen hdmi switcher its offering me less quality signal. sorry about that.
    Why sorry? Not your fault and you simply describe what you perceive - my goal was to describe in proper way what you described as this is malfunction not intentional way how HDMI switcher works. IMHO i can say that seem your HDMI switcher is faulty - try to disconnect other HDMI cables and verify if this still behave same as before. There is some malfunction that affecting DDC lines. (this is my first guess). HDMI is poorly designed interface.
    Quote Quote  
  8. EDID miscommunication with some switchers? For example, on one TV I have a HDMI switch between a computer and the TV. If I turn on the computer before the TV I get a 1024x768 picture. If I turn on the TV before the computer I get 1920x1080. Different brightness may be RGB vs. YUV transmission and settings.
    Quote Quote  
  9. Originally Posted by jagabo View Post
    EDID miscommunication with some switchers? For example, on one TV I have a HDMI switch between a computer and the TV. If I turn on the computer before the TV I get a 1024x768 picture. If I turn on the TV before the computer I get 1920x1080. Different brightness may be RGB vs. YUV transmission and settings.
    It can be even more quirky - for example Hot Plug signal not changing at all and EDID handshake not even properly started thus HDMI falling to fallback scenario but this imply 720x480 (or even 640x480 with full RGB quantization range i.e. pure DVI). After many years of testing of consumer devices i have strong conclusion that HDMI is poorly designed standard where plenty areas are not covered and left only to developer experience...
    I saw badly designed HDMI on very reputable, large companies that are considered as high tech engineering leader. Everything is possible...
    Quote Quote  



Similar Threads

Visit our sponsor! Try DVDFab and backup Blu-rays!