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  1. I use OBS-Studio to record set-topbox via Avermedia CV 710 U3.With CRF settings in x264 option as 8 , As per my hardware limitations which is the better option to use the for deinterlacing: Input 1080i 50 HZ

    (1) Yadif 2x and output selected at 25 FPS at cpu preset very fast
    (2) Yadif 2x and output selected at 50 FPS with cpu preset superfast
    (2) Yadif x and output selected at 25 with cpu preset very fast

    Plz note that yadif 2x is frame doubler BUT i have to choose video output as 25 FPS to avoid frame drops at cpu preset very fast. Please advise me.
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  2. It partially depends on what type of content you are recording. If you recording something like fast action sports, you're going to want 50fps

    i7-4702MQ? How about quick sync at 50fps as another option ?
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  3. If your primary concern is quality, don't deinterlace at all. And, if possible, don't capture as x264, even with a CRF of 8.

    If it has to be deinterlaced, do it later on at your computer where you can use better deinterlacers. Try and capture exactly what is being broadcast.
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    Originally Posted by Rajesh Singh View Post
    I use OBS-Studio to record set-topbox via Avermedia CV 710 U3.With CRF settings in x264 option as 8 , As per my hardware limitations which is the better option to use the for deinterlacing: Input 1080i 50 HZ

    (1) Yadif 2x and output selected at 25 FPS at cpu preset very fast
    (2) Yadif 2x and output selected at 50 FPS with cpu preset superfast
    (2) Yadif x and output selected at 25 with cpu preset very fast

    Plz note that yadif 2x is frame doubler BUT i have to choose video output as 25 FPS to avoid frame drops at cpu preset very fast. Please advise me.
    Why do you believe that the Avermedia CV 710 U3 provides interlaced output from 1080i input? Avermedia's specs for the device say all output is progressive.
    Input:
    640 x 480 (60p) / 720 x 480 (60p/60i) / 720 x 576 (50p/50i) / 800 x 600 (60p)
    1024 x 768 (60p) / 1280 x 720 (60p/50P)
    1280 x 768 (60p) / 1280 x 800 (60p) / 1280 x 1024 (60p)
    1360 x 768 (60p) / 1440 x 900 (60p) / 1680 x 1050 (60p)
    1920 x 1080 (60p/50p/30p/25p/24p/60i/50i)
    Capture:
    640 x 480 (60p) / 720 x 480 (60p/30p) / 720 x 576 (50p/25p) / 800 x 600 (60p)
    1024 x 768 (60p/30p) / 1280 x 720p (60p/50p/30p/25p)
    1280 x 768 (60p/30p) / 1280 x 800 (60p/30p) / 1280 x 1024 (60p/30p)
    1360 x 768 (60p/30p) / 1440 x 900 (60p/30p) / 1680 x 1050 (60p/30p)
    1920 x 1080 (60p/50p/30p/25p/24p)
    I mentioned that the Avermedia CV 710 U3 deinterlaces 1080i input and frame decimates it to 1080p30 in your other thread: https://forum.videohelp.com/threads/384423-Bitrate-of-HDTV-set-top-box-signals-for-FUL...-HD-broadcasts
    Last edited by usually_quiet; 30th Jul 2017 at 23:57.
    Ignore list: hello_hello, tried, TechLord, Snoopy329
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  5. Hi usually-quiet, the progressive output which you see in the specs of Avermedia CV 710 is spec for CV710 used with proprietary Avermedia Recentral software . When using OBS-studio, if i don't deinterlace i get a completely interlaced output, although the file spec as per mediainfo is progressive. The problem is for recording 60FPS(I have confirmed now from different recording tests that as EXPECTED, recording at 25 or 50 FPS results in frame drops every 1.02 seconds in my 60 HZ laptop display, so 50 Hz is out of question), I have to lower the CRF from 8 to 16-17 to avoid getting massive frame drops without using ultrafast cpu preset which i avoid.
    Plz explain whats the difference between these FOUR scenarios(preferably in context of OBS Studio):

    (1) Deinterlacing 1080i/60 Hz using yadif and selecting output as 1080p/30FPS
    (2) Deinterlacing 1080i/60 Hz using yadif2x and selecting output as 1080p/30FPS
    (3)Deinterlacing 1080i/60 Hz using yadif and selecting output as 1080p/60FPS
    (4)Deinterlacing 1080i/60 Hz using yadif2x and selecting output as 1080p/60FPS


    The content i record is movie(original 24FPS which might be teleclined/interlaced by broadcasters to broadcasting frequency.

    Also its CONFIRMED that there's no such thing as PAL/NTSC for HD broadcasts because all set-topbox including mine TATA-skyHD have both options as output(50/60 Hz). I do agree that in PAl counttries like India, power supply is 50 Hz but there'eno confirmation whether that plays a role in any so called native broadcast frequency in Digital Tv broadcasts.
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  6. Originally Posted by manono View Post
    If your primary concern is quality, don't deinterlace at all. And, if possible, don't capture as x264, even with a CRF of 8.

    If it has to be deinterlaced, do it later on at your computer where you can use better deinterlacers. Try and capture exactly what is being broadcast.
    Hi Monono, i was under the assumption that software x264 encoding is best in OBS-Studio. If not, then whats the better option ?
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  7. Originally Posted by poisondeathray View Post
    It partially depends on what type of content you are recording. If you recording something like fast action sports, you're going to want 50fps

    i7-4702MQ? How about quick sync at 50fps as another option ?
    Hi bro, quality wise , x264 software encoding is supposed to be best as per my limited knowledge. NVENC ranks second and Quick-sync last . Correct me if I am wrong.
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  8. Originally Posted by Rajesh Singh View Post
    Originally Posted by poisondeathray View Post
    It partially depends on what type of content you are recording. If you recording something like fast action sports, you're going to want 50fps

    i7-4702MQ? How about quick sync at 50fps as another option ?
    Hi bro, quality wise , x264 software encoding is supposed to be best as per my limited knowledge. NVENC ranks second and Quick-sync last . Correct me if I am wrong.
    It is in general yes, but not if you're dropping frames, or you use crappy settings . QS is generally better than NVEnc quality wise

    If I'm understanding you correctly, you said you were using crf 8. At crf 8, the filesizes will be fairly large. At those bitrate ranges, I doubt anyone would be able to tell the difference in quality between those 3 encoders




    The content i record is movie(original 24FPS which might be teleclined/interlaced by broadcasters to broadcasting frequency.

    Also its CONFIRMED that there's no such thing as PAL/NTSC for HD broadcasts because all set-topbox including mine TATA-skyHD have both options as output(50/60 Hz). I do agree that in PAl counttries like India, power supply is 50 Hz but there'eno confirmation whether that plays a role in any so called native broadcast frequency in Digital Tv broadcasts.
    In North America, if it was 24fps film you wouldn't deinterlace , you would need to IVTC to recover the original film frames . Deinterlacing will just destroy the quality. And do you see 24 is not evenly divisible into 30 or 60 (the rates you were planning to record at)? You're going to get a judder choppy cadence unless you remove duplicates

    In India, you might have some bizarre field blending. You might have to use other processing like a field deblender. This would be non real time processing (you'd do it at a second stage) . Manono would know more. Or maybe if you uploaded a sample with no processing it would be a better idea to clarify exactly what you're dealing with
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  9. Originally Posted by poisondeathray View Post
    Originally Posted by Rajesh Singh View Post
    Originally Posted by poisondeathray View Post
    It partially depends on what type of content you are recording. If you recording something like fast action sports, you're going to want 50fps

    i7-4702MQ? How about quick sync at 50fps as another option ?
    Hi bro, quality wise , x264 software encoding is supposed to be best as per my limited knowledge. NVENC ranks second and Quick-sync last . Correct me if I am wrong.
    It is in general yes, but not if you're dropping frames, or you use crappy settings . QS is generally better than NVEnc quality wise

    If I'm understanding you correctly, you said you were using crf 8. At crf 8, the filesizes will be fairly large. At those bitrate ranges, I doubt anyone would be able to tell the difference in quality between those 3 encoders




    The content i record is movie(original 24FPS which might be teleclined/interlaced by broadcasters to broadcasting frequency.

    Also its CONFIRMED that there's no such thing as PAL/NTSC for HD broadcasts because all set-topbox including mine TATA-skyHD have both options as output(50/60 Hz). I do agree that in PAl counttries like India, power supply is 50 Hz but there'eno confirmation whether that plays a role in any so called native broadcast frequency in Digital Tv broadcasts.
    In North America, if it was 24fps film you wouldn't deinterlace , you would need to IVTC to recover the original film frames . Deinterlacing will just destroy the quality. And do you see 24 is not evenly divisible into 30 or 60 (the rates you were planning to record at)? You're going to get a judder choppy cadence unless you remove duplicates

    In India, you might have some bizarre field blending. You might have to use other processing like a field deblender. This would be non real time processing (you'd do it at a second stage) . Manono would know more. Or maybe if you uploaded a sample with no processing it would be a better idea to clarify exactly what you're dealing with
    Hi poisondeathray ,
    Yes i am recording at crf=8 with cpu preset very fast. Below that (either crf or cpu preset i get frame drops) . At this setting i am getting bitrates of around 40 Mbps. i can't compress lower by cpu preset because it causes frame drops. i don't want to go higher bitrates because I am assuming that broadcasts are done at around 12-16 Mbps so there'e no point in inflating files further. There'd no option for IVTC in OBS Studio while recording .I would have SURELY DONE that . I can only enable IVTC during playback in Jriver Media Center by selecting force film mode option in deinterlacing options of MadVR renderer. I will upload snapshots/sample soon tonight to make things clear . thanks for helping me out.
    Last edited by Rajesh Singh; 31st Jul 2017 at 10:59.
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  10. I tried recording at 24 FPS. i wanted to ask that in query too . Will it be OK to record 1080i/60 Hz input which definitely contains an original 24 FPS film at 24 FPS deinterlaced output. You see there'e no option of IVTC in OBS Studio. I understand that for 24 FPS best display option is 24 Hz or 120 HZ but i have to manage with my 60 Hz laptop display.As per that 60 Hz , i am prefering 30/60FPS because 25/50FPS gives frame drops. 24 FPS gives(as EXPECTED) frame repeats due to to original 2:3 pull up of 24 FPS by broadcasting studios. What is the better option to record such content for 60 Hz display.
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  11. Originally Posted by Rajesh Singh View Post
    I tried recording at 24 FPS. i wanted to ask that in query too . Will it be OK to record 1080i/60 Hz input which definitely contains an original 24 FPS film at 24 FPS deinterlaced output. You see there'e no option of IVTC in OBS Studio. I understand that for 24 FPS best display option is 24 Hz or 120 HZ but i have to manage with my 60 Hz laptop display.As per that 60 Hz , i am prefering 30/60FPS because 25/50FPS gives frame drops. 24 FPS gives(as EXPECTED) frame repeats due to to original 2:3 pull up of 24 FPS by broadcasting studios. What is the better option to record such content for 60 Hz display.
    If that's true ,you would have to record 60Hz , the process it later with other programs. If you can record it interlaced ("MBAFF") if obs gives you that option it would be actually better - because some hardware can detect the cadence and IVTC . If you record it "progressive" , you will see combing and scan lines because the software or hardware player will "think" it's progressive. The best way would be to record interlaced, and properly process it later to give proper 24p - so you get full resolution and there are no mistakes in playing. When you deinterlace progressive content, in general you lose ~1/2 the spatial resolution
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  12. Also its CONFIRMED that there's no such thing as PAL/NTSC for HD broadcasts because all set-topbox including mine TATA-skyHD have both options as output(50/60 Hz). I do agree that in PAl counttries like India, power supply is 50 Hz but there's no confirmation whether that plays a role in any so called native broadcast frequency in Digital Tv broadcasts.
    I'm pretty sure you are wrong here. You are talking about your set top box decoded output, not original signal which is I think 25i (50Hz) in India. I remember I once had sample from one Tata Sky channel someone recorded once and posted here and it was 25i).

    Many set-top boxes today have abilities like frame rate conversion from 25 to 30, 50-60 or upscaling/downscaling SD to HD, HD to SD and deinterlacing. Sure you could record 30 or 60 fps but that video will contain eiter duplicate or blended frames from your STB conversion. Bottom line you should record at 25 if you can.


    Also, last time I tried OBS you can't record 25 in OBS studio. It's an application made for capturing console or PC gaming and not cable/satellite set top box. You are using software that was made for streaming games. You should use Virtualdub or AmaRecTV with some lossless or visually lossless compression and after that offline compression with x264 instead of OBS using x264.
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  13. Originally Posted by badyu17 View Post
    Also its CONFIRMED that there's no such thing as PAL/NTSC for HD broadcasts because all set-topbox including mine TATA-skyHD have both options as output(50/60 Hz). I do agree that in PAl counttries like India, power supply is 50 Hz but there's no confirmation whether that plays a role in any so called native broadcast frequency in Digital Tv broadcasts.
    I'm pretty sure you are wrong here. You are talking about your set top box decoded output, not original signal which is I think 25i (50Hz) in India. I remember I once had sample from one Tata Sky channel someone recorded once and posted here and it was 25i).

    Many set-top boxes today have abilities like frame rate conversion from 25 to 30, 50-60 or upscaling/downscaling SD to HD, HD to SD and deinterlacing. Sure you could record 30 or 60 fps but that video will contain eiter duplicate or blended frames from your STB conversion. Bottom line you should record at 25 if you can.


    Also, last time I tried OBS you can't record 25 in OBS studio. It's an application made for capturing console or PC gaming and not cable/satellite set top box. You are using software that was made for streaming games. You should use Virtualdub or AmaRecTV with some lossless or visually lossless compression and after that offline compression with x264 instead of OBS using x264.
    Hi badyu
    thanks for your valuable suggestions. i will try virtualdub and AmaRecTv BTW i was always doubtful of OBS Studio for recording interlaced high quality but yes, it can give output of 25 fps in its video setting option(Select Integers option).
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    Originally Posted by Rajesh Singh View Post
    Hi usually-quiet, the progressive output which you see in the specs of Avermedia CV 710 is spec for CV710 used with proprietary Avermedia Recentral software . When using OBS-studio, if i don't deinterlace i get a completely interlaced output, although the file spec as per mediainfo is progressive. The problem is for recording 60FPS(I have confirmed now from different recording tests that as EXPECTED, recording at 25 or 50 FPS results in frame drops every 1.02 seconds in my 60 HZ laptop display, so 50 Hz is out of question), I have to lower the CRF from 8 to 16-17 to avoid getting massive frame drops without using ultrafast cpu preset which i avoid
    Fair enough.

    If you recall, I mentioned in your other thread that the software you have been using is designed for streaming, which normally uses progressive video at 30fps, 50 fps, or 60fps. Since you can get interlaced output from this device, I add my name to the list of those recommending using different software for capturing and capturing as interlaced video. I agree with the suggestions you received regarding software. They are good ones.

    .
    Originally Posted by Rajesh Singh View Post
    Plz explain whats the difference between these FOUR scenarios(preferably in context of OBS Studio):

    (1) Deinterlacing 1080i/60 Hz using yadif and selecting output as 1080p/30FPS
    (2) Deinterlacing 1080i/60 Hz using yadif2x and selecting output as 1080p/30FPS
    (3)Deinterlacing 1080i/60 Hz using yadif and selecting output as 1080p/60FPS
    (4)Deinterlacing 1080i/60 Hz using yadif2x and selecting output as 1080p/60FPS
    I don't use OBS because I am not interesting in streaming video. I can only guess at what it actually does.

    When yadif does "single rate" deinterlacing, it converts interlaced video at 25fps (which has 50 fields per second) into progressive video at 25fps, discarding half of the fields in the process instead of converting them into frames.

    When yadif does "double rate" deinterlacing, it converts interlaced video at 25fps (which has 50 fields per second) into progressive video at 50fps, converting all fields into frames.

    yadif recreates missing lines in fields by interpolating them from pixels in the previous frame, current frame and the next frame, so it produces better results than bob deinterlacing, but it is a slower process than bob deinterlacing, but still fast enough to use in real time. QTGMC produces better results than yadif, and always does "double rate" deinterlacing, but it is too slow to use in real time.

    I think yadif(2x) is explicitly yadif "double rate" deinterlacing, but at 30fps, every other deinterlaced frame would be discarded.
    Last edited by usually_quiet; 31st Jul 2017 at 13:48. Reason: corrected wrong explaination of what yadif does. Grammar
    Ignore list: hello_hello, tried, TechLord, Snoopy329
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