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#61
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Is VLC 3.0.3 for Windows 7?
"J. P. Gilliver (John)" wrote:
[...] For example, I know there are lossless, for example, _rotations_ for JPEG, For any decent renderer, JPEG images do not need to be rotated, because the orientation can be set by bits in the EXIF part of the JPEG file. IrfanView - or possibly one of the plugins for it; I tend to think of the combination as just IrfanView - offers lossless JPEG crop and rotation. IrfanView is an example of such a renderer: Options - Properties/Settings... - JPG / PCD / GIF - JPEG-Load: - tick 'Auto-rotate image according to EXIF info (if available)'. I don't know if IrfanView can 'rotate' a picture by changing just the EXIF info and not touching the rest of the file. It probably can, but I didn't find it straight-away (I use other software to 'rotate' JPEG pictures). |
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#62
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"film vs CMOS" -- "Mental State"?
On 8/12/2018 5:18 PM, Mr. Man-wai Chang wrote:
On 8/12/2018 5:14 PM, Steve Hough wrote: nospam was thinking very hard : what if you stopped posting rubbish? Why not stop feeding the troll? Switching topic to mental state... If you don't wanna continue to answer, just say so. You can also throw me to Google Search. I wanna remind you that this is not your company, definitely not a court room. This is just a causal chat. Your honor and income will not be affected. Do you always do that when you were still in schools? Oh well... amazed me. Maybe I am too lucky not studying in your schools. -- @~@ Remain silent! Drink, Blink, Stretch! Live long and prosper!! / v \ Simplicity is Beauty! /( _ )\ May the Force and farces be with you! ^ ^ (x86_64 Ubuntu 9.10) Linux 2.6.39.3 不借貸! 不詐騙! 不*錢! 不援交! 不打交! 不打劫! 不自殺! 不求神! 請考慮綜援 (CSSA): http://www.swd.gov.hk/tc/index/site_...sub_addressesa |
#63
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how original is an original image?
"Mr. Man-wai Chang" wrote in newskn96p$qar$1
@toylet.eternal-september.org: On 8/12/2018 2:08 AM, nospam wrote: In article , Mr. Man-wai Chang wrote: But how do you determine how close a digital image get to the original without a reference? You have to have a control as in experiment! the reference is the original In a court trial, how do you do that? You cannot take the physical reality into a court... there is also the time factor. Whatever happened in reality might not repeat itself before the court. Example scenerio: I'm out with my trusty movie/video camera, and happen to capture a driver running a red light/stop sign and striking your car. I only discover this when I receive the file back from developing/watch the video. Being the good citizen that I am, I contact the police and tell them about the evidence I have. `They come and take said evidence/or make a copy of said evidence. I sign a sworn statement concerning how I optained the original. The evidence is placed into a sealed bag/container, and I sign as the originator/owner, and the person receiving the evidence signs as the one receiving it from me. They then sign it into the evidence storage at their office. Anyone making a copy or otherwise having that evidence in their possession outside of the evidence storage area has to sign for the original and why they had access/possession of it. This process continues until the evidence is used in court, if it is. Along with the evidence comes the 'chain of evidence possession' documenting its origin and any and all accesses to it up to the time it is presented as evidence in court. This is the accepted means of documenting how the evidence was created and accessed the veracity and and protection of the evidence all along the process. If there is a question of the accuracy of any copies made the 'chain of possession' documentation and expert testimony is used to resolve it. Any analog process of duplication incurrs some loss. A digital proccess of dublication of a digital original can occur without loss, depending on the specifics of the process used to create the 'duplicate'. |
#64
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Is VLC 3.0.3 for Windows 7?
"Paul" wrote in message
news Char Jackson wrote: On Sat, 11 Aug 2018 00:50:41 -0400, Paul wrote: J. P. Gilliver (John) wrote: Thanks. I was just wondering if, once the initial compression had been done, any of the various formats can be converted into each other without _further_ loss. Sounds like you don't know - fair enough, nor do I, hence my asking the question! The "formats" part can be broken down into two pieces. The outside part is the "container". .mkv , .mov , .avi are containers Inside the container are video and audio codecs. SNIP Hi Paul, I know what you wanted to say but that last part didn't come out right. There are no codecs inside the container. That would be quite inefficient. ;-) Otherwise, excellent summary. Yeah, that should have been "video and audio streams". I think what he meant were "video and audio streams, compressed with codecs that the decoding device (PC, TV, PVR, dedicated box, etc) will already have". The crucial thing is that the container can contain streams which are compressed with various codecs, so you can't infer the codec from the container. For example, .ts files recorded from broadcast TV can be either MPEG2/MPEG (video/audio) or else H264/AAC(LATM) (video/audio) depending whether they are recorded from a DVB-T or DVB-T2 multiplex. Likewise for ..wtv (WIndows Media Centre) files. I think .mpg files are always encoded with MPEG2 encording; I've never seen any that are H264. However I have seen high-def (1920x1080) compressed with MPEG2, even if H264 is far more common. |
#65
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film vs CMOS
On 8/11/2018 11:17 PM, Mr. Man-wai Chang wrote:
On 8/12/2018 1:19 AM, nospam wrote: Should we always compare 135 film against CMOS sensors of different size? always the same size format. otherwise it's not a valid comparison. In reality, we just need to do the job right and fair, not about comparison or superiority! What if... a big what if.... all CMOS on Earth were fried by solar storm? Maybe that explained why a man is up there in ISS. This is sort of an answer to the original question. quote: "The resolution of film images depends upon the area of film used to record the image (35 mm, medium format or large format) and the film speed. Estimates of a photograph's resolution taken with a 35 mm film camera vary. More information may be recorded if a fine-grain film is used, while the use of poor-quality optics or coarse-grained film may yield lower image resolution. A 36 mm × 24 mm frame of ISO 100-speed film was initially estimated to contain the equivalent of 20 million pixels,[6] or approximately 23,000 pixels per square mm. " In my experience, my 12 mega pixel Olympus camera gives me pictures as good as my Old Miranda Camera with a good slide film. With a chemical camera the resolution is limited to the grain size in a film. However with a print the quality of the paper the images is printed on will also affect the resolution in the print With a digital in my opinion has a large range of light conditions under which you can get good images. With all of the above, in both types of camera it is the lens system. Poor quality lens gives poor quality images regardless of the film or CMOS. As an example I have a cheap phone with a 1.3 megapixel camera. It gives me consistently better pictures than my tablet which has a 2 megapixel CMOS. This is evident in that with the phone I can easily get readable images of printed pages, but impossible with the tablet. In other words with lens systems you can not make a silk purse out of of a sow's ear, no matter how you process. |
#66
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film vs CMOS
"knuttle" wrote in message
news With a chemical camera the resolution is limited to the grain size in a film. However with a print the quality of the paper the images is printed on will also affect the resolution in the print With a digital in my opinion has a large range of light conditions under which you can get good images. With all of the above, in both types of camera it is the lens system. Poor quality lens gives poor quality images regardless of the film or CMOS. As an example I have a cheap phone with a 1.3 megapixel camera. It gives me consistently better pictures than my tablet which has a 2 megapixel CMOS. This is evident in that with the phone I can easily get readable images of printed pages, but impossible with the tablet. The other thing with digital is that the quality of the image is affected by the post-processing and the amount of noise that the sensor generates. Noise increases with increased amplification (higher ISO setting) and with reduced pixel size: a phone with a small sensor (so each pixel is smaller) will produce more noise than an SLR with a larger sensor with the same resolution. Often this is masked by post-processing which manifests itself as localised blurring of detail. My SLR at 3200 ASA produces a less noisy picture than my phone camera at a much lower ISO setting. The SLR's lens is also better, but that's a separate issue. One other factor is that phone cameras are often a fixed focal length, so if you zoom in you are using a progressively smaller area of the sensor which increases noise and (even more so) decreases resolution - just like making a print from a progressively smaller part of the negative. Digital also has the advantage that it is much easier to correct for different colours of light (sunlight / cloud / daylight fluorescent / warm white fluorescent / LED / tungsten), either manually with presets or automatically. And the sensitivity of the sensor doesn't change at very short or very long exposures: with film you had to make corrections both for exposure and colour cast due to "reciprocity failure" whereby the normal rule of "reduce shutter speed by one stop requires opening up aperture by one stop" no longer applies. With negative film it wasn't too much of an issue because neg film can produce a usable print from a negative with more under or over exposure, and colour cast can be corrected at printing, whereas slide film has much less exposure latitude and has no opportunity for correcting colour cast, apart from by copying onto a new slide with a filter in place, or by scanning to digital. I was surprised at how much correction scanning does allow. I took some night-time photos of an illuminated building and grossly overexposed (I was guessing). The slides are very pale. When I scanned them (about 30 years later!), I could correct for this increasing the contrast so the darkest pale tones became nearly black and the lightest, almost clear film, became white. Given that exposure at night is very subjective anyway (there is no one "correct" exposure) this was good enough to produce better copies than the original. If I'd been shooting on digital, I'd have seen the results of my guesses immediately and corrected accordingly, either by looking at the result or looking at the histogram (proportion of pixels with each brightness - should look *very roughly* like a symmetrical bell-shaped curve, assuming a typical scene, which night pictures often aren't because of bright lights or shadows which are outside the range of what you want to reproduce well (ie it's much more acceptable have some parts which are totally black or bleached maxed-out white). |
#67
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film vs CMOS
In article , NY
wrote: The other thing with digital is that the quality of the image is affected by the post-processing and the amount of noise that the sensor generates. film is also affected by the processing and also the type of film. Noise increases with increased amplification (higher ISO setting) and with reduced pixel size: a phone with a small sensor (so each pixel is smaller) will produce more noise than an SLR with a larger sensor with the same resolution. film is similar. high iso films have more grain, while smaller formats need to be enlarged more for the same size print. |
#68
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Is VLC 3.0.3 for Windows 7?
On 11/08/2018 17:50, nospam wrote:
In article , Mr. Man-wai Chang wrote: But how do you get a 100% TRUE lossless original? Using good, old film-based cameras? film is more lossy than digital. I bet there are many film cameras that are way way better than my first ever webcam - 320x240 resolution fixed focus. Looked horrible in anything except bright sunlight. Luckily is was cheap so I wasn't that bothered. Nevertheless IT WAS DIGITAL. -- Brian Gregory (in England). |
#69
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Is VLC 3.0.3 for Windows 7?
On 06/08/2018 19:10, mike wrote:
Win 7-32. I tried updating to Version 3.something and had playback issues. Version 2.2.8 is reported to be the last version to support .wtv files.* That seems to work.* Probably a good idea to archive that version if you use media center. Many of my *.wtv files play fine in VLC 3.0.3 (64 bit version). There are a few where the sound doesn't work but I can't work out exactly why it doesn't work. I think they are files where I've had trouble finding much at all that can deal with the sound correctly. -- Brian Gregory (in England). |
#70
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Is VLC 3.0.3 for Windows 7?
On 09/08/2018 22:38, Tim wrote:
If for some reason you don't like 3.0.3 I still have 2.2.8 and 3.0.0 on my hard drive. Old versions of VLC are he https://get.videolan.org/vlc/ All the way back to around 2004 IIRC. -- Brian Gregory (in England). |
#71
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Is VLC 3.0.3 for Windows 7?
Brian Gregory wrote:
On 11/08/2018 17:50, nospam wrote: In article , Mr. Man-wai Chang wrote: But how do you get a 100% TRUE lossless original? Using good, old film-based cameras? film is more lossy than digital. I bet there are many film cameras that are way way better than my first ever webcam - 320x240 resolution fixed focus. Looked horrible in anything except bright sunlight. Luckily is was cheap so I wasn't that bothered. Nevertheless IT WAS DIGITAL. If you have a static scene, and you run the webcam in "picture" mode instead of "video" mode, you can actually take two pictures with a bad webcam, and average them in Photoshop as (A+B)/2 and the sensor noise will be attenuated. I did some pictures for a user manual that way. Shot about 70 images, and averaged them to improve the quality. It was before I got a digital camera. In testing, averaging an excessive number of images doesn't help. I tried for example, averaging 16 images in NIHimage, and it really doesn't help all that much. But if you place your camera on a tripod, and the scene is static, and you shoot the two pictures one after the other, then averaging the two pictures reduces the sensor noise. The biggest improvement comes by using two images. It still isn't digital camera quality, but at least it's a small improvement. Sony HAD sensors are better than your average webcam. And you're not likely to get one for $10 :-) Sony has no interest in supplying the $10 webcam market. https://en.wikipedia.org/wiki/HAD_CCD https://en.wikipedia.org/wiki/Hole_accumulation_diode That's what you'd like to see in a webcam. Paul |
#72
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Is VLC 3.0.3 for Windows 7?
mike wrote:
On 8/5/2018 7:36 PM, Shadow wrote: On Sun, 05 Aug 2018 18:51:08 -0400, wrote: I am currently running 2.2.4 Weatherwax on a 64 bit Win 7 machine. Should (can I) upgrade to VLC 3.0.3? Version 2.2.8 here. I did try a more recent version, but got crashes, so reverted. If 2.2.4 works, use it. []'s Win 7-32. I tried updating to Version 3.something and had playback issues. Version 2.2.8 is reported to be the last version to support .wtv files. That seems to work. Probably a good idea to archive that version if you use media center. ffplay will play .wtv files. You have to specify the streams though, as I have stations here with four streams in the file and stations with five streams in the file. It could be the difference is subtitles. ("Audio stream 2" "Video stream 3" 704x480 resolution) ffplay -ast 2 -vst 3 -x 704 -y 480 some.wtv Part of the ffmpeg package. And what should happen, is .wtv files that are encrypted, your options should be a lot more limited. Paul |
#73
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Is VLC 3.0.3 for Windows 7?
In message , Frank Slootweg
writes: "J. P. Gilliver (John)" wrote: [...] For example, I know there are lossless, for example, _rotations_ for JPEG, For any decent renderer, JPEG images do not need to be rotated, because the orientation can be set by bits in the EXIF part of the JPEG file. IrfanView - or possibly one of the plugins for it; I tend to think of the combination as just IrfanView - offers lossless JPEG crop and rotation. IrfanView is an example of such a renderer: Options - Properties/Settings... - JPG / PCD / GIF - JPEG-Load: - tick 'Auto-rotate image according to EXIF info (if available)'. That "(if available)" is the significant point. There are JPEG images around that don't have that flag - either they predate its definition, or the camera they were taken on did not have an orientation sensor. I don't know if IrfanView can 'rotate' a picture by changing just the EXIF info and not touching the rest of the file. It probably can, but I didn't find it straight-away (I use other software to 'rotate' JPEG pictures). I've always _assumed_ IV's "lossless JPEG rotate" actually rearranged the pixel data. (Could easily be established by turning _off_ the auto-rotate setting, then trying such a rotate.) -- J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf Easy reading is damned hard writing. -Nathaniel Hawthorne, writer (1804-1864) |
#74
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Is VLC 3.0.3 for Windows 7?
"Paul" wrote in message
news And what should happen, is .wtv files that are encrypted, your options should be a lot more limited. I've not found any WTV that seem to be encrypted - or at least, I've not found any files that can't be played and edited with VLC and VideoReDo respectively. That's for both SD (720x576x25) and HD (1920x1080x25), recored from DVB-T and DVB-T2 in the UK. Likewise for TS files recorded using NextPVR - no apparent encryption or restrictions for SD or HD. The only device that cripples HD is a dedicated PVR which has the ability to export its recordings to TS format on a USB device. That option is enabled for SD recordings but disabled (maybe due to copy-protection restrictions) for HD recordings. |
#75
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Is VLC 3.0.3 for Windows 7?
"J. P. Gilliver (John)" wrote:
In message , Frank Slootweg writes: "J. P. Gilliver (John)" wrote: [...] For example, I know there are lossless, for example, _rotations_ for JPEG, For any decent renderer, JPEG images do not need to be rotated, because the orientation can be set by bits in the EXIF part of the JPEG file. IrfanView - or possibly one of the plugins for it; I tend to think of the combination as just IrfanView - offers lossless JPEG crop and rotation. IrfanView is an example of such a renderer: Options - Properties/Settings... - JPG / PCD / GIF - JPEG-Load: - tick 'Auto-rotate image according to EXIF info (if available)'. That "(if available)" is the significant point. There are JPEG images around that don't have that flag - either they predate its definition, or the camera they were taken on did not have an orientation sensor. EXIF exists since the early 2000's, at least since 2003. AFAIK, EXIF has always had "that flag". The only issues are if "that flag" has been *set* or/and if "that flag" is *honoured* by the renderer. Whether "that flag" is/can_be set by the camera is irrelevant to my point. My point is that "that flag" makes it unneccesary to actually rotate the data in the picture itself. I don't know if IrfanView can 'rotate' a picture by changing just the EXIF info and not touching the rest of the file. It probably can, but I didn't find it straight-away (I use other software to 'rotate' JPEG pictures). I've always _assumed_ IV's "lossless JPEG rotate" actually rearranged the pixel data. (Could easily be established by turning _off_ the auto-rotate setting, then trying such a rotate.) I think/assume that IrfanView can just set "that flag", but, as I said, I haven't yet found how. IrfanView is very powerful, but that also means that simple things are sometimes hard to find/do. |
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