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    #16
    1920x1080 settings from Papas (not the 1440x1080 stretched but the true 1920x1080)

    with 4:2:2 color turned on, I got 2 seconds of video, that was it before the camera stopped recording, it didn't freeze, but it automatically stops recording.

    Quality Settings: Same as previouse post
    87.6 mbps (approx)

    Original file:
    https://stillmaninteriors.dc1.netfir...s/P1080391.MOV



    *** Marker: DQT (xFFDB) ***
    Define a Quantization Table.
    OFFSET: 0x00115CA2
    Table length = 132
    ----
    Precision=8 bits
    Destination ID=0 (Luminance)
    DQT, Row #0: 2 2 2 2 5 3 8 8
    DQT, Row #1: 2 2 2 2 3 6 8 8
    DQT, Row #2: 2 2 3 3 3 6 11 9
    DQT, Row #3: 2 3 3 5 8 9 14 14
    DQT, Row #4: 2 3 5 8 9 11 8 16
    DQT, Row #5: 6 5 8 9 11 14 11 14
    DQT, Row #6: 3 9 13 11 14 16 14 13
    DQT, Row #7: 9 11 13 13 16 16 14 14
    Approx quality factor = 92.95 (scaling=14.10 variance=11.76)
    ----
    Precision=8 bits
    Destination ID=1 (Chrominance)
    DQT, Row #0: 3 2 3 3 14 14 14 14
    DQT, Row #1: 3 3 6 8 14 14 14 14
    DQT, Row #2: 3 6 9 14 14 14 14 14
    DQT, Row #3: 3 14 14 14 14 14 14 14
    DQT, Row #4: 9 14 14 14 14 14 14 14
    DQT, Row #5: 14 14 14 14 14 14 14 14
    DQT, Row #6: 14 14 14 14 14 14 14 14
    DQT, Row #7: 14 14 14 14 14 14 14 14
    Approx quality factor = 92.90 (scaling=14.21 variance=6.19)
    GH13, Sound Devices 702, Schoeps CMC641, COS11d-BP Lav, FOCAL CMS40 Monitor, Rycote Softie, Audio Technica 1800 wireless system, 20mm f1.7, 14mm f2.5, 50mm f1.4 FD, 200m F2.8 FD, 4x4 filter set, Schneider .03 ND Grad, Schneider .9 ND Hard Grad, Schneider Polarizing Filter,

    Comment


      #17
      Yes, look at my explanation in main thread.
      Bitrate with Pappas settings is too much even for normal 1920, only 1440.
      Even 1440 in 422 require much lower quality settings.

      Comment


        #18
        ok

        Ok, thanks Tester13 but I am wondering if this data is helping you? Or do we already have what you need?

        IB
        GH13, Sound Devices 702, Schoeps CMC641, COS11d-BP Lav, FOCAL CMS40 Monitor, Rycote Softie, Audio Technica 1800 wireless system, 20mm f1.7, 14mm f2.5, 50mm f1.4 FD, 200m F2.8 FD, 4x4 filter set, Schneider .03 ND Grad, Schneider .9 ND Hard Grad, Schneider Polarizing Filter,

        Comment


          #19
          Originally posted by IanB View Post
          Ok, thanks Tester13 but I am wondering if this data is helping you? Or do we already have what you need?
          IB
          Quantization tables are lowest possible level to change quality.
          Each table is directly associated to JPEG quality setting.
          They all are scaled from source table.

          Comment


            #20
            This may already be done, and it may not help you

            Here are the Q tables from the latest 4:2:2 color patch with 720 mjpg and the papas settings.




            *** Marker: DQT (xFFDB) ***
            Define a Quantization Table.
            OFFSET: 0x0025C6A2
            Table length = 132
            ----
            Precision=8 bits
            Destination ID=0 (Luminance)
            DQT, Row #0: 1 1 1 1 2 1 3 3
            DQT, Row #1: 1 1 1 1 1 2 3 3
            DQT, Row #2: 1 1 1 1 1 2 4 3
            DQT, Row #3: 1 1 1 2 3 3 5 5
            DQT, Row #4: 1 1 2 3 3 4 3 5
            DQT, Row #5: 2 2 3 3 4 5 4 5
            DQT, Row #6: 1 3 4 4 5 5 5 4
            DQT, Row #7: 3 4 4 4 5 5 5 5
            Approx quality factor = 97.33 (scaling=5.34 variance=2.68)
            ----
            Precision=8 bits
            Destination ID=1 (Chrominance)
            DQT, Row #0: 1 1 1 1 5 5 5 5
            DQT, Row #1: 1 1 2 3 5 5 5 5
            DQT, Row #2: 1 2 3 5 5 5 5 5
            DQT, Row #3: 1 5 5 5 5 5 5 5
            DQT, Row #4: 3 5 5 5 5 5 5 5
            DQT, Row #5: 5 5 5 5 5 5 5 5
            DQT, Row #6: 5 5 5 5 5 5 5 5
            DQT, Row #7: 5 5 5 5 5 5 5 5
            Approx quality factor = 97.48 (scaling=5.04 variance=0.70)
            GH13, Sound Devices 702, Schoeps CMC641, COS11d-BP Lav, FOCAL CMS40 Monitor, Rycote Softie, Audio Technica 1800 wireless system, 20mm f1.7, 14mm f2.5, 50mm f1.4 FD, 200m F2.8 FD, 4x4 filter set, Schneider .03 ND Grad, Schneider .9 ND Hard Grad, Schneider Polarizing Filter,

            Comment


              #21
              Downloaded an original 720p MJPEG clip from vimeo (clip 12515307) with the following settings:

              Quality settings (E1 to E4) - 352, 220, 200, 184
              Table settings (E1 to E4) - 24, 24, 24, 24

              MediaInfo says 54.5 Mbps

              Code:
              JPEGsnoop 1.2.0 by Calvin Hass
                www.impulseadventure.com/photo/
                -------------------------------
              
                Filename: [C:\WINDOWS\Desktop\tester13\720p MJPEG.mov]
                Filesize: [292424830] Bytes
              
              Start Offset: 0x00007F00
              *** Marker: SOI (xFFD8) ***
                OFFSET: 0x00007F00
               
              *** Marker: DQT (xFFDB) ***
                Define a Quantization Table.
                OFFSET: 0x00007F02
                Table length = 132
                ----
                Precision=8 bits
                Destination ID=0 (Luminance)
                  DQT, Row #0:   2   2   2   2   5   4   9   9 
                  DQT, Row #1:   2   2   2   2   4   7   9   9 
                  DQT, Row #2:   2   2   4   4   4   7  12  11 
                  DQT, Row #3:   2   4   4   5   9  11  16  16 
                  DQT, Row #4:   2   4   5   9  11  12   9  18 
                  DQT, Row #5:   7   5   9  11  12  16  12  16 
                  DQT, Row #6:   4  11  14  12  16  18  16  14 
                  DQT, Row #7:  11  12  14  14  18  18  16  16 
                  Approx quality factor = 92.07 (scaling=15.85 variance=15.32)
                ----
                Precision=8 bits
                Destination ID=1 (Chrominance)
                  DQT, Row #0:   4   2   4   4  16  16  16  16 
                  DQT, Row #1:   4   4   7   9  16  16  16  16 
                  DQT, Row #2:   4   7  11  16  16  16  16  16 
                  DQT, Row #3:   4  16  16  16  16  16  16  16 
                  DQT, Row #4:  11  16  16  16  16  16  16  16 
                  DQT, Row #5:  16  16  16  16  16  16  16  16 
                  DQT, Row #6:  16  16  16  16  16  16  16  16 
                  DQT, Row #7:  16  16  16  16  16  16  16  16 
                  Approx quality factor = 91.74 (scaling=16.51 variance=8.99)
               
              *** Marker: SOF0 (Baseline DCT) (xFFC0) ***
                OFFSET: 0x00007F88
                Frame header length = 17
                Precision = 8
                Number of Lines = 720
                Samples per Line = 1280
                Image Size = 1280 x 720
                Raw Image Orientation = Landscape
                Number of Img components = 3
                  Component[1]: ID=0x01, Samp Fac=0x22 (Subsamp 1 x 1), Quant Tbl Sel=0x00 (Lum: Y)
                  Component[2]: ID=0x02, Samp Fac=0x11 (Subsamp 2 x 2), Quant Tbl Sel=0x01 (Chrom: Cb)
                  Component[3]: ID=0x03, Samp Fac=0x11 (Subsamp 2 x 2), Quant Tbl Sel=0x01 (Chrom: Cr)

              Comment


                #22
                http://www.dpreview.co.uk/maint/prin...kond2x&page=13
                anything beyond quality factor 90 is just a waste of bitrate....
                http://www.impulseadventure.com/phot...lity_irfan.gif
                the big one...

                Comment


                  #23
                  Originally posted by vladszp View Post
                  http://www.dpreview.co.uk/maint/prin...kond2x&page=13
                  anything beyond quality factor 90 is just a waste of bitrate....
                  http://www.impulseadventure.com/phot...lity_irfan.gif
                  the big one...
                  OK, and how this relate to MJPEG encoder research?
                  Quality factor is just subjective number made from Q table.
                  Any Q table is used to remove some DCT info.
                  So, it is never waste of space.
                  If anyone shoots highly detailed nature scenes even very high quality JPEG images can show artefacts.

                  Comment


                    #24
                    Hello!

                    I just noticed one thing you might find interesting: entry "MJPEG Encoder 30fps->Xfps" is somehow affecting AVCHD recording as well.

                    I use AVCHD Bitrate "C" settings and it works perfectly in 1080p25 ("Native 24/25p" enabled). But as soon as I enable "MJPEG Encoder 30fps->Xfps" with "25" as entry (I live in PAL country), I get problems with AVCHD and camera stops recording after couple of seconds. MJPEG recording works (MJPEG bitrate was tuned to "manageable" levels I know camera would support, like 60Mbit or so) but it's able to record only couple of seconds at the time. It will record for longer time but as soon as I stop recording, it will hang for 10 secs and then ask me to reboot the camera by switching on/off.

                    Keeping "MJPEG Encoder 30fps->Xfps" unchecked will let AVCHD work. Checking it will make AVCHD fail with same bitrate.

                    Hypotesis: "MJPEG Encoder 30fps->Xfps" set to 25 seems to be affecting more than MJPEG.

                    Comment


                      #25
                      I think you're on to something. If I set both the 30fps->24fps, and the 30fps->Xfps to 24, and nothing else, StreamEye displays the video on a split screen with squashed versions of the clip on the top and bottom of the screen. Windows Media Player, however, shows it correctly. Obviously something changed that StreamEyE deals with differently than Media Player.

                      Chris

                      Comment


                        #26
                        All tests are made with
                        GH1 + 20 mm 1.7 pancake in M and manual focus mode
                        Shutter 1/50, Arperture f5.0, ISO 100
                        STANDARD -2, -2, -2, -2
                        Card: 16 GB Sandisk Extreme Class 10 card

                        JPEGSnoop doesn’t work reliable with alalyzing the GH1 MJPEG files so the 1280 x 720 JPEG thumbnail that accompanies any movie file was analyzed. As Vitaliy already said those thumbnails have the very same compression quality applied as the movie file. The only lossy process in (M)JPEG compression is the quantisation step after the Discrete Cosinus Transformation (DCT). Low values in the 8 x 8 Quantisation Tables result in higher image quality. A low detail scene and a high detail scene was recorded for each setting and the JPEGSnoop quality factor as well as the bitrate was noted.



                        Setting quality only
                        Code:
                        QUESTION: Does setting quality alone affect quantisation table?
                        ANSWER: No
                        
                        FACTORY SETTINGS Firmware 1.32
                        Q: Factory (128, 110, 100, 92)
                        T: Factory (133, 146, 150, 155)
                        Low detailed scene: 83.09
                        High detailed scene: Only 19.16 !!!
                        Playback in camera: YES
                        
                        REVERSED quality settings Firmware 1.33
                        Q: 92, 100, 110, 128
                        T: Factory (133, 146, 150, 155)
                        Low detailed scene: 83.09
                        High detailed scene: 19.16
                        Playback in camera: YES
                        
                        EQUAL quality settings Firmware 1.34
                        Q: 128, 128, 128, 128
                        T: Factory (133, 146, 150, 155)
                        Low detailed scene: 83.09
                        High detailed scene: 19.16
                        Playback in camera: YES
                        CONCLUSION
                        Setting Quality alone has no effect on quantisation table used
                        Camera chooses very high compression for high detailed scenes.
                        GH1 uses a variable MJPEG compression to avoid too high bitrates on high detailed scenes. Low detailed scene scenes are less compressed. High detailed scene ones more.

                        Setting table only
                        Code:
                        QUESTION: Do table settings affect quantisation table?
                        ANSWER: Absolutely
                        
                        FACTORY SETTINGS Firmware 1.32
                        Q: Factory (128, 110, 100, 92)
                        T: Factory (133, 146, 150, 155)
                        Low detailed scene: 83.09 / 8 mbps
                        High detailed scene: only 19.16 !!! / 37 mbps
                        Playback in camera: YES
                        Note: Very high compression on high detailed scene to bring data rate down to 37 mbps. 
                        
                        REVERSED TABLE FACTORY SETTINGS Firmware 1.35
                        Q: Factory (128, 110, 100, 92)
                        T: 155, 150, 146, 133
                        Low detailed scene: 80.06
                        High detailed scene: 19.16 
                        Playback in camera: YES
                        Note: no effect
                        
                        EQUAL TABLE SETTINGS Firmware 1.36
                        Q: Factory (128, 110, 100, 92)
                        T: 133, 133, 133, 133
                        Low detailed scene: 83.09 / 0.6 mbps
                        High detailed scene: 19.16 / 35.7 mbps
                        Playback in camera: YES
                        Note: no effect
                        
                        LOW TABLE SETTINGS Firmware 1.37
                        Q: Factory (128, 110, 100, 92)
                        T: 24, 24, 24, 24
                        Low detailed scene: 97.33 / 28 mbps !!!
                        High detailed scene: 19.16 / 35.7 mbps
                        Playback in camera: YES
                        Note: Only compression of low detail scene  is improved
                        
                        LOWEST TABLE SETTINGS Firmware 1.38
                        Q: Factory (128, 110, 100, 92)
                        T: 0, 0, 0, 0
                        Low detailed scene: 100!!! / 62 mbps / Movie OK
                        High detailed scene: 100!!! / 63 mbps / Movie is black!!!
                        Playback in camera: NO!!!
                        Note: “Lossless”, Luma and Chroma quantisation tables are filled with the number one
                        
                        2,2,2,2 TABLE SETTING Firmware 1.39
                        Q: Factory (128, 110, 100, 92)
                        T: 2, 2, 2, 2
                        Low detailed scene: 100!!! / 60 mbps  / Movie OK
                        High detailed scene: 79 / 63 mbps  / Movie is black
                        Playback in camera: NO
                        Note: Camera starts to increase compression on high detailed scene. 
                        
                        4,4,4,4 TABLE SETTING Firmware 1.40
                        Q: Factory (128, 110, 100, 92)
                        T: 4, 4, 4, 4
                        Low detailed scene: 98 / 52 mbps  / Movie OK
                        High detailed scene: 56 / 63 mbps  / Movie OK
                        Playback in camera: NO
                        Note: Even more compression on high detailed scene
                        
                        5,5,5,5 TABLE SETTING Firmware 1.41
                        Q: Factory (128, 110, 100, 92)
                        T: 5, 5, 5, 5
                        Low detailed scene: 98 / 37 mbps  / Movie OK
                        High detailed scene: 45 / 56 mbps  / Movie OK
                        Playback in camera: LOW: YES, HIGH: NO
                        Note: max. clip length with this settings: 7 minutes - 2 GB
                        CONCLUSION
                        Table settings have direct influence on the quantisation table used. With 5,5,5,5 low detailed scene compression quality is very good (98). For high detailed scenes the camera still chokes the bitrate by choosing a lower quality quantisation table but quality improves from 19 - 37 mbps to 45 - 56 mbps.
                        Only low detail scenes play back in camera. There seems to be a limit around 37 mbps with my card. Clips below this limit play back fine.

                        Setting quality and table
                        Code:
                        QUESTION: Is the quality settings sequence “128,110,100,92” the bitrate choke?
                        ANSWER: It seems so. Doubling the values makes the bitrate choke less aggressive and allows lower compression of high detailed scenes
                        
                        NO CHOKE? QUALITY SETTING Firmware 1.42
                        Q: 128, 128, 128, 128
                        T: 5, 5, 5, 5
                        Low detailed scene: 98 / 37 mbps  / Movie OK
                        High detailed scene: 44 / 56 mbps  / Movie OK
                        Playback in camera: NO
                        Note: Fail. Has no effect on quantisation table chosen
                        
                        DOUBLED QUALITY / T5 SETTING Firmware 1.43
                        Q: 256, 220, 200, 184
                        T: 5, 5, 5, 5
                        Low detailed scene: 100!!! / 61!!! mbps  / Movie OK
                        High detailed scene: 86!!! / 88!!! mbps  / Movie OK
                        Playback in camera: NO
                        4:2:0 chroma subsampling
                        Note: Excellent low detail and better high detail compression
                        
                        4:2:2 + DOUBLED Q / T5 SETTING Firmware 1.44
                        Q: 256, 220, 200, 184
                        T: 5, 5, 5, 5
                        Low detailed scene: 100 / 67 mbps  / Movie OK
                        High detailed scene: 82 / 77 mbps  / Movie OK
                        4:2:2 chroma subsampling
                        Playback in camera: NO
                        Note: Not much difference. Camera seems to record fine.
                        max. Individual clip length with these settings: about 4 minutes - 2 GB 
                        16 GB card will store 32 minutes of footage.
                        Real live scenes show 92 / 70 mbps
                        
                        PappasArts + 4:2:2 SETTING Firmware 1.46
                        Q: 384, 330, 300, 276
                        T: 24, 24, 24, 24
                        Low detailed scene: 97 / 34 mbps  / Movie OK
                        High detailed scene: 81 / 75 mbps  / Movie recording stopped after 3s!!!
                        4:2:2 chroma subsampling
                        Playback in camera: LOW: YES, HIGH: NO
                        Note: No improvement over DOUBLED Q / T5 SETTING plus camera failed to record high detailed secene after 3s.
                        
                        4:2:2 + DOUBLED Q / T4 SETTING Firmware 1.47
                        Q: 256, 220, 200, 184
                        T: 4, 4,4, 4
                        Low detailed scene: 100 / 80 mbps  / Movie recording fails after a few seconds!
                        High detailed scene: 85 / 80 mbps  / Movie OK
                        4:2:2 chroma subsampling
                        Playback in camera: NO
                        Note: Fail
                        
                        4:2:2 + 1.5 X Q / T4 SETTING Firmware 1.48
                        Q: 192, 165, 150, 138
                        T: 4, 4,4, 4
                        Low detailed scene: 100 / 55 mbps  / Movie OK
                        High detailed scene: 74 / 82 mbps  / Movie OK
                        4:2:2 chroma subsampling
                        Playback in camera: NO
                        Note: High detail better than with DOUBLED Q / T5
                        Real live scenes show 94 / 70 mbps
                        
                        4:2:2 + 1.75 X Q / T4 SETTING Firmware 1.49
                        Q: 224, 192, 175, 161
                        T: 4, 4,4, 4
                        Low detailed scene: 100 / 72 mbps  / Movie OK
                        High detailed scene: 81 / 84 mbps  / Movie OK
                        4:2:2 chroma subsampling
                        Playback in camera: NO
                        Note: Similar to DOUBLED Q / T5 setting
                        Real live scenes show 85 - 97 quality
                        CONCLUSION
                        The table / quality relationship remains a mystery to me.
                        At the moment I use the 4:2:2 + 1.75 X Q / T4 SETTING without problems.

                        We would need a much better source image before the MJPEG compression to fully qualify such high compression quality settings. The video source image is quite soft and degraded because of the fast downsampling method (pixel binning?) used. The still photo source is much better downsampled.
                        Last edited by Martin Koch; 06-25-2010, 11:41 AM.

                        Comment


                          #27
                          I can only applaud to this testing work.

                          Comment


                            #28
                            More tests and still no clue.

                            Code:
                            4:2:2 + Paul Shields  SETTINGS Firmware 1.50
                            Q: 256, 256, 256, 256
                            T: 5, 5, 5, 5
                            Low detailed scene: 100 / 89 mbps  / Movie OK
                            High detailed scene: 82 / 100!!! mbps  / Movie recording failed after a few seconds
                            4:2:2 chroma subsampling
                            Playback in camera: NO
                            Note: 
                            
                            4:2:2 + 128 / 5  SETTING Firmware 1.52
                            Q: 128, 128, 128, 128
                            T: 5, 5, 5, 5
                            Low detailed scene: 95 / 28 mbps  / Movie OK 
                            High detailed scene: 36 / 52 mbps  / Movie OK
                            4:2:2 chroma subsampling
                            Playback in camera: LOW: YES, HIGH: NO
                            Note: Bitrate choke is still active and seems to be implemented somewhere else
                            
                            4:2:2 + 0 / 5  SETTING Firmware 1.53
                            Q: 0, 0, 0, 0
                            T: 5, 5, 5, 5
                            Camera refuses to record. Corrupted movie files on card. No thumbnail files
                            Note: Display shows 29 min 59 sec recording time (European PAL Limit)
                            
                            4:2:2 + 10 / 5  SETTING Firmware 1.54
                            Q: 10, 10, 10, 10
                            T: 5, 5, 5, 5
                            Low detailed scene: 19 / 0.5 mbps  / Movie OK BUT VERY LOW QUALITY
                            High detailed scene: 19 / 0.5 mbps  / Movie is BLACK!!!
                            4:2:2 chroma subsampling
                            Playback in camera: LOW: YES, HIGH: NO
                            Note: Display shows 29 min 59 sec recording time 
                            
                            4:2:2 + 256, 256, 220, 200 / 5  SETTING Firmware 1.55
                            Q: 256, 256, 220, 200
                            T: 5, 5, 5, 5
                            Low detailed scene: 100 / 83 mbps  / Movie OK
                            High detailed scene: 82 / 85 mbps  / Movie OK
                            4:2:2 chroma subsampling
                            Playback in camera: NO
                            Note: Display shows about 4 min recording time 
                            
                            4:2:2 + 256, 256, 256, 220 / 5  SETTING Firmware 1.56
                            Q: 256, 256, 256, 220
                            T: 5, 5, 5, 5
                            Low detailed scene: 100 / 85 mbps  / Movie recording failed after a few seconds
                            High detailed scene: 82 / 85 mbps  / Movie recording failed after a few seconds
                            4:2:2 chroma subsampling
                            Playback in camera: NO
                            Note: Same tables but Movie recording failes after a few seconds
                            
                            4:2:2 + 200 / 5  SETTING Firmware 1.57
                            Q: 200, 200, 200, 200
                            T: 5, 5, 5, 5
                            Low detailed scene: 98.15 / 56 mbps  / Movie OK
                            High detailed scene: “only” 69 / 77 mbps  / Movie OK
                            4:2:2 chroma subsampling
                            Playback in camera: NO
                            Note: Display shows about 5 min clip recording time
                            Should be a very stable setting
                            
                            
                            4:2:2 + 215 / 5  SETTING Firmware 1.58
                            Q: 215, 215, 215, 215
                            T: 5, 5, 5, 5
                            Low detailed scene: 98.32 / 77 mbps  / Movie OK
                            High detailed scene: 74 / 83 mbps  / Movie OK
                            4:2:2 chroma subsampling
                            Playback in camera: NO
                            Note: Display shows about 5 min clip recording time
                            Quantisation table of low detailed scene is filled with “Ones” and “Twos”
                            Quality 74 is nice for high detailed scenes
                            The last 4:2:2 + 215 / 5 SETTING should be a very stable setting for any Class 10 card
                            Tested with Film mode Smooth -2 -2 -2 -2, continuous autofocus (AFC) and 1/50 shutter speed. No problems. Real life scenes are around 70 mbps
                            To me this 720p MJPEG looks as good as 720p50 with "c" settings.

                            Comment


                              #29
                              I understand this thread is aggressively moderated, but I wanted to post some findings that you may or may not find useful. I was unsure if testers really sift thru the noise on the main hack forum, so I'm providing a repost. Jpegsnoop is suggesting very high quality results.

                              Observations...

                              T = 1, resulting jpeg is roughly 1/4 complete.
                              T = 2, resulting jpeg is roughly 1/2 complete
                              T = 3, restulting jpeg is roughly 3/4 complete

                              As previously noted, using any tables 0-3 result in a quicktime which is black on playback. So obviously, T = 4 is the lowest setting that provides a completed and valid jpeg + mov. Might T have something to do with how the image is scanned? Anyway, I used this as my base point, as low T values always seem to perform well.

                              My initial goal was to figure out what quality settings could provide continuous playback on a Sandisk 8GB Extreme Class 10.

                              Q1=188, T1=4
                              Q2=188, T2=4
                              Q3=188, T3=4
                              Q4=188, T4=4

                              This resuted in recording of the star chart and real world examples with no errors at 75+mbps for complex scenes. There was still a fair degree of compression though, so I began to think about the logic of the system.

                              Q=188, T=4 for all stages 1-4 suggests the codec is always operating against the same threshold when dealing with it's variable bit rate. It suggests that for complex scenes, this is the max is can handle (on my card), however it leaves less complex scenes wanted more bits thrown at it. Odds are, the codec is constantly trying to get the most bits in there until there is a overflow and it must test the next lower Q level.

                              So what if we up the thresholds on Q1-Q3, and let Q4 be our last line of defense?

                              I came up with these settings...

                              Q1=400, T1 = 4
                              Q2=300, T2 = 4
                              Q3=250, T3 = 4
                              Q4=188, T3 = 4


                              The idea was to keep the thresholds very high (and throw more at simpler scenes), but if necessary back them down to the maximum my card could handle when a scene gets too complex. It seems like the codec is always trying to keep the threshold as high as possible.

                              Sorry for the lack of wonderful shots with flowers in bloom. It was gloomy outside morning, however I've tested these setting with complex natural scenes as well. Thus far, it's been working flawless.

                              Nostalgic Film Mode: Contrast -2, Sharpness -2, Saturation 0, Noise Reduction 0



                              ----------

                              Precision=8 bits
                              Destination ID=0 (Luminance)
                              DQT, Row #0: 1 1 1 1 1 1 1 1
                              DQT, Row #1: 1 1 1 1 1 1 1 1
                              DQT, Row #2: 1 1 1 1 1 1 1 1
                              DQT, Row #3: 1 1 1 1 1 1 1 1
                              DQT, Row #4: 1 1 1 1 1 1 1 1
                              DQT, Row #5: 1 1 1 1 1 1 1 1
                              DQT, Row #6: 1 1 1 1 1 1 1 1
                              DQT, Row #7: 1 1 1 1 1 1 1 1
                              Approx quality factor = 100.00 (scaling=2.99 variance=6.13)
                              ----
                              Precision=8 bits
                              Destination ID=1 (Chrominance)
                              DQT, Row #0: 1 1 1 1 1 1 1 1
                              DQT, Row #1: 1 1 1 1 1 1 1 1
                              DQT, Row #2: 1 1 1 1 1 1 1 1
                              DQT, Row #3: 1 1 1 1 1 1 1 1
                              DQT, Row #4: 1 1 1 1 1 1 1 1
                              DQT, Row #5: 1 1 1 1 1 1 1 1
                              DQT, Row #6: 1 1 1 1 1 1 1 1
                              DQT, Row #7: 1 1 1 1 1 1 1 1
                              Approx quality factor = 100.00 (scaling=1.54 variance=1.58)

                              Compression stats:
                              Compression Ratio: 5.13:1
                              Bits per pixel: 4.68:1





                              ----------

                              Precision=8 bits
                              Destination ID=0 (Luminance)
                              DQT, Row #0: 1 1 1 1 1 1 1 1
                              DQT, Row #1: 1 1 1 1 1 1 1 1
                              DQT, Row #2: 1 1 1 1 1 1 2 2
                              DQT, Row #3: 1 1 1 1 1 2 2 2
                              DQT, Row #4: 1 1 1 1 2 2 1 3
                              DQT, Row #5: 1 1 1 2 2 2 2 2
                              DQT, Row #6: 1 2 2 2 2 3 2 2
                              DQT, Row #7: 2 2 2 2 3 3 2 2
                              Approx quality factor = 98.22 (scaling=3.57 variance=4.57)
                              ----
                              Precision=8 bits
                              Destination ID=1 (Chrominance)
                              DQT, Row #0: 1 1 1 1 2 2 2 2
                              DQT, Row #1: 1 1 1 1 2 2 2 2
                              DQT, Row #2: 1 1 2 2 2 2 2 2
                              DQT, Row #3: 1 2 2 2 2 2 2 2
                              DQT, Row #4: 2 2 2 2 2 2 2 2
                              DQT, Row #5: 2 2 2 2 2 2 2 2
                              DQT, Row #6: 2 2 2 2 2 2 2 2
                              DQT, Row #7: 2 2 2 2 2 2 2 2
                              Approx quality factor = 98.80 (scaling=2.39 variance=0.91)

                              Compression stats:
                              Compression Ratio: 5.74:1
                              Bits per pixel: 4.18:1




                              ----------

                              Precision=8 bits
                              Destination ID=0 (Luminance)
                              DQT, Row #0: 1 1 1 1 1 1 1 1
                              DQT, Row #1: 1 1 1 1 1 1 1 1
                              DQT, Row #2: 1 1 1 1 1 1 1 1
                              DQT, Row #3: 1 1 1 1 1 1 1 1
                              DQT, Row #4: 1 1 1 1 1 1 1 1
                              DQT, Row #5: 1 1 1 1 1 1 1 1
                              DQT, Row #6: 1 1 1 1 1 1 1 1
                              DQT, Row #7: 1 1 1 1 1 1 1 1
                              Approx quality factor = 100.00 (scaling=2.99 variance=6.13)
                              ----
                              Precision=8 bits
                              Destination ID=1 (Chrominance)
                              DQT, Row #0: 1 1 1 1 1 1 1 1
                              DQT, Row #1: 1 1 1 1 1 1 1 1
                              DQT, Row #2: 1 1 1 1 1 1 1 1
                              DQT, Row #3: 1 1 1 1 1 1 1 1
                              DQT, Row #4: 1 1 1 1 1 1 1 1
                              DQT, Row #5: 1 1 1 1 1 1 1 1
                              DQT, Row #6: 1 1 1 1 1 1 1 1
                              DQT, Row #7: 1 1 1 1 1 1 1 1
                              Approx quality factor = 100.00 (scaling=1.54 variance=1.58)

                              Compression stats:
                              Compression Ratio: 5.93:1
                              Bits per pixel: 4.05:1




                              ----------

                              Precision=8 bits
                              Destination ID=0 (Luminance)
                              DQT, Row #0: 1 1 1 1 1 1 1 1
                              DQT, Row #1: 1 1 1 1 1 1 1 1
                              DQT, Row #2: 1 1 1 1 1 1 1 1
                              DQT, Row #3: 1 1 1 1 1 1 1 1
                              DQT, Row #4: 1 1 1 1 1 1 1 1
                              DQT, Row #5: 1 1 1 1 1 1 1 1
                              DQT, Row #6: 1 1 1 1 1 1 1 1
                              DQT, Row #7: 1 1 1 1 1 1 1 1
                              Approx quality factor = 100.00 (scaling=2.99 variance=6.13)
                              ----
                              Precision=8 bits
                              Destination ID=1 (Chrominance)
                              DQT, Row #0: 1 1 1 1 1 1 1 1
                              DQT, Row #1: 1 1 1 1 1 1 1 1
                              DQT, Row #2: 1 1 1 1 1 1 1 1
                              DQT, Row #3: 1 1 1 1 1 1 1 1
                              DQT, Row #4: 1 1 1 1 1 1 1 1
                              DQT, Row #5: 1 1 1 1 1 1 1 1
                              DQT, Row #6: 1 1 1 1 1 1 1 1
                              DQT, Row #7: 1 1 1 1 1 1 1 1
                              Approx quality factor = 100.00 (scaling=1.54 variance=1.58)

                              Compression stats:
                              Compression Ratio: 5.24:1
                              Bits per pixel: 4.58:1




                              ----------

                              Precision=8 bits
                              Destination ID=0 (Luminance)
                              DQT, Row #0: 1 1 1 1 1 1 1 1
                              DQT, Row #1: 1 1 1 1 1 1 1 1
                              DQT, Row #2: 1 1 1 1 1 1 1 1
                              DQT, Row #3: 1 1 1 1 1 1 1 1
                              DQT, Row #4: 1 1 1 1 1 1 1 1
                              DQT, Row #5: 1 1 1 1 1 1 1 1
                              DQT, Row #6: 1 1 1 1 1 1 1 1
                              DQT, Row #7: 1 1 1 1 1 1 1 1
                              Approx quality factor = 100.00 (scaling=2.99 variance=6.13)
                              ----
                              Precision=8 bits
                              Destination ID=1 (Chrominance)
                              DQT, Row #0: 1 1 1 1 1 1 1 1
                              DQT, Row #1: 1 1 1 1 1 1 1 1
                              DQT, Row #2: 1 1 1 1 1 1 1 1
                              DQT, Row #3: 1 1 1 1 1 1 1 1
                              DQT, Row #4: 1 1 1 1 1 1 1 1
                              DQT, Row #5: 1 1 1 1 1 1 1 1
                              DQT, Row #6: 1 1 1 1 1 1 1 1
                              DQT, Row #7: 1 1 1 1 1 1 1 1
                              Approx quality factor = 100.00 (scaling=1.54 variance=1.58)

                              Compression stats:
                              Compression Ratio: 8.01:1
                              Bits per pixel: 3.00:1

                              Comment


                                #30
                                FACTORY SETTINGS
                                Q: 128, 110, 100, 92
                                T: 133, 146, 150, 155
                                Low detailed scene: 83.09 / 0.6 mbps / PLAYBACK OK / MOVIE OK
                                High detailed scene: 19.16 / 36.15 mbps / PLAYBACK OK / MOVIE OK
                                4:2:0
                                Clip recording time display: 8m 20s


                                CUT AFTER E1
                                Q: 128, 110, 100, 92
                                T: 133, 146, 150, 155
                                Low detailed scene: 83.09 / 0.6 mbps / PLAYBACK OK / MOVIE OK
                                High detailed scene: 19.16 / 37.12 mbps / PLAYBACK OK / MOVIE OK
                                4:2:0
                                Clip recording time display: 8m 20s

                                Cut after E1 doesn't seem to have an effect.

                                Comment

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