Giveaway of the Day Forums

1. 

   mikiem2
   Moderator

   WonderFox Video to Picture Converter is a small, portable app based on the LibAV code libraries [libav.org], where you can also pick up newer builds if you're feeling adventurous & want to try swapping out a couple few files to see if there's any improvement. It takes a video file and saves X number of pictures a second, where X is a number you set. Its calculations are a bit off, showing more frames at 29.98 pix per second than the video had. It lets you save animated GIFs, though there's not enough tools really to do that right. Uncompressed .tif files, probably the best option for quality to import into an image editor, can report an inaccurate dpi, while software disagreed whether the GIF files were really GIF or png [they are 8bit with a 256 color pallet]. Myself, I'll hang onto it & maybe see if I can get some interesting stop motion type stuff out of it.

   The traditional reason to turn a video into a series of stills was so those stills could be manipulated in something like an image editor, then chained back together again in a new video file. It's not as popular as it once was because it's not as needed as it once was, but there's still stuff that's pretty hard to accomplish any other way. I think maybe the example the most people have heard of is painting out the wires suspending actors in mid-air, though several image editors nowadays will import video, letting you paint frame by frame without going to the bother of converting everything to stills first. A lot of stuff that used to be edited this way is also now done using green screen techniques, where everything in the frame that's a particular color is replaced, e.g. the screen showing weather maps on TV during the forecast.

   IMHO the reason most home users or video hobbyists convert video to a series of stills is to use batch processing in an image editor, for stuff like color correction, sharpening, noise removal etc. that otherwise might take more expensive video editing software. VirtualDub was mentioned, & that's one of the free tools that's been often used to create the stills & reassemble them, but the problem with that is VirtualDub has limited import formats it'll accept, so you often have to install, learn, & use Avisynth -- WonderFox Video to Picture Converter makes that end of things easier. And since Wonderfox software is portable, there's not a big reason not to give it a try.

   As far as using stills from video as some sort of replacement for photos, it generally doesn't work so well because most people don't have source video that's anywhere near the sharpness & clarity they get using just the camera in their cell phone to take pictures. A cell or tablet or camera takes a bit of time processing & then writing the image to your memory card or wherever that image is stored -- the fastest they can manage is measured in pictures per minute. Unless you've got Very expensive gear, when you shoot or record video a camera, cell, &/or tablet is going to capture images that are much lower quality so they can be captured & stored at 24-30 fps. Different companies have tried developing software that averages the pictures from several frames to get one, higher quality still, but AFAIK no one has ever achieved more than a minor improvement.

   Posted 10 years ago #
2. 

   mikiem2
   Moderator

   #5: "So I tried it on an HD m2ts file, output as “BEST” – ani gif isn’t that great. Many artifacts. So I tried .tga frames as they suppose to give best quality … but than I found no good interlaced frames. I can’t find any DE-intelace option .
   This is a major drawback of such software"

   The problem is the video -- not the software. Most video that you can get your hands on is just not that great when it comes to image quality, but at 24 - 30 fps you don't notice. RE: Interlace & Deinterlace, if the video you have is actually interlaced, you can usually get the best results deinterlacing using various different methods in Avisynth or filters in VirtualDub, though some folks I think have done work in this area using Handbrake -- the idea is you get more total image data shooting interlaced, which you then use Handbrake on to achieve higher quality progressive frames than you could otherwise. That said, if you're going to wind up going back to video once you've processed the frames as still images, you might process the individual fields as 1/2 height stills & reassemble them into interlaced video afterwards. 1 interlaced frame = 2 fields.

   * * *

   #7: "I believe you are thinking of VirtualDub... It is limited to avi video, but with the zillions of converters offered here, that should not be a huge drawback."

   You don't want to convert your video to avi just to disassemble it into individual images -- you'll lose far too much quality. The traditional way you get whatever format of video into VirtualDub is to use Avisynth. After installing Avisynth you write a few lines of scripting in a plain text file you name with an .avs extension -- for something like this there are plenty of examples on-line you can copy/paste. An example would be a single line script:
   DirectShowSource("Your Path & Filename Here",The fps For That File Here,video=true)

   When you open that .avs file in VirtualDub or whatever program, it will use whatever Direct Show [DS] software you have installed that's available & that can decode that video for playback, say in Windows Media Player. Avisynth will open that file, read the picture data frame by frame, feeding it to VirtualDub as if VirtualDub had opened the video file itself. That skips re-encoding the video & writing it to disk as an avi file, avoiding that quality loss & usually saving quite a bit of time.

   If you do decide you need a avi file for whatever reason, Do Not use ffmpeg or anything based on it if at all possible, & that includes the converters that have been on GOTD. Ffmpeg includes and uses Xvid. Xvid is a mp4 video codec that's compatible with old versions of DivX, & was designed to be an alternative to formats like Windows Media [.wmv] for final distribution back before there were better alternatives like AVC. Instead use a [near] lossless format for your avi file(s) -- I use the UT Video codec, but Avid has a nice codec too that's capable of HD that they give away free. What I use, FWIW, is Avisynth -> VirtualDub, having V/Dub write a avi file using UT Video.

   Posted 10 years ago #
3. 

   mikiem2
   Moderator

   Maybe ironically I checked the GOTD download page to see if comments had been posted or not -- running behind I thought maybe I'll save time by not posting them to the forum, since it didn't seem that big a deal in this case -- the GOTD was a rather niche app. I should have just posted in the forum & not looked. ;) Incorrect stuff bothers me -- can't help it. I don't want to argue or imply any sort of disrespect, and I don't have a big ego, wasn't offended by the phrase "approximate knowledge" [I had to Google it not being an "Adventure Time" fan]. But I did want to post correct info -- readers can check or research as wanted/needed, but I think it helps when they know something may be incorrect so they know to ignore it or look it up as they choose.

   My original comment [above to #7] was to the effect that you want to use as lossless a format as possible when you're storing content that you'll work on later -- that applies to still images [e.g. raw or tif or psd etc. rather than jpeg], and audio [.wav or .w64 rather than mp3 or aac], and it applies to video. Windows Media can actually work, as can mpg2 with the right settings, but most in the industry use something like UT Video, or the HD codecs from Avid etc. You definitely do not want to use one of the mpeg 4 type codecs as you'll throw out too much data needlessly -- those include older plane Jane .wmv, older DivX, Xvid etc. The ffmpeg-based converters that have been on GOTD along with any others that I've tried, e.g. XMedia Recode, won't let you use something like UTVideo, even though you've got it installed in Windows, but most often they use Xvid instead [XMedia Recode does give you a few more options besides Xvid, but nothing I'd use for intermediates nowadays]. As general advice I said & still say, avoid ffmpeg as possible for storing intermediates -- it offers little to no benefits for that particular use that I'm aware of, & will probably limit your flexibility.

   Someone apparently took offense at that... Now I must apologize to everyone that didn't read papin's post -- in that case ignore this please. [I know I wish I could have, but bad info bothers me. :( ] Nonetheless, maybe there's some info in here that's worthwhile.

   "1. ffmpeg does not use xvid unless you tell it to do so. If you don’t have the xvid codec installed, you can use ffmpeg nonetheless. Example:
   ffmpeg -c <codec name> ..."

   Running ffmpeg from the command line [DOS prompt], which is what you're talking about, the basic syntax is ffmpeg -i [InputFileHere] -c [CodecNameHere] [OutputFileNameHere]. It may or may not work, depending on if it wants to talk to the installed codec you specified. Without naming any codec the default is FMP4 -- it adds a fair amount of compression [1.5 GB lossless avi to 19 MB]. There's not a lot of info on it, but as there isn't that much in the way of original mp4 code freely available it's probably similar under the hood to Xvid, which along with DivX started out as a bit of early code from Microsoft for their .wmv format. [According to Wikipedia, ffmpeg devs did come up with a few great things, but they *borrowed* even more.] At any rate you're correct, if you want to run ffmpeg from the command line, specifying a lossless codec that you've installed, *maybe* ffmpeg will work to write your intermediate avi. In context however, I'm not sure how many people reading this will want to hunt up a compiled win32 version of ffmpeg to use on the command line that may or may not work when they try it.

   "2. MP4 is a container, not a codec; it can store audio, video, subtitles, and whatever you want (e.g. multiple audio files)."

   That's incorrect... Mpeg4 is a video spec. often/usually called mp4. It's not like mpg2, where most mpg2 is similar to what's on DVDs, but includes quite a variety of similar encoding techniques or technologies. Mpeg4 video can be in all sorts of container files, .mov, .avi, .m2ts etc., though the official container for *some* mpeg4 video is .mp4, & most types of mpeg4 video will work in a .mp4 container. AVC for example can reside in a file named .mp4, .avi, .mov, .m2ts, .ts, and on & on, & yes, AVC adheres to, is covered under part of the mpg4 spec.

   http://en.wikipedia.org/wiki/MPEG-4
   "Most of the features included in MPEG-4 are left to individual developers to decide whether to implement them."
   http://en.wikipedia.org/wiki/MPEG-4_Part_14
   "MPEG-4 Part 14 or MP4 is a digital multimedia format..." "The only official filename extension for MPEG-4 Part 14 files is .mp4..."

   "3. xvid is not a an alternative to WMV and will never be, because WMV is Microsoft proprietary format for video encoded with Microsoft’s proprietary codecs whilst xvid is free software (unlike divx). It is not a “mp4 video codec” either as you wrote it. Xvid is an alternative to DivX, and certainly not compatible with it. By “compatible” I suppose you meant a device (e.g. a DVD player) able to read both xvid and divx encoded videos. For example, many Microsoft devices are compatible only with WMV."

   http://www.xvid.org/FAQ.14.0.html
   "Xvid is a MPEG-4 video codec for PC. "

   When Microsoft was initially working on .wmv some folks used some of the code & with a bit of re-working it became the earliest version of DivX. DivX went on over time to become pay-ware, & then a regular company. Before DivX moved beyond Xvid they could be used interchangeably -- the 4CC codes that Windows went by could be either/or. DivX could & can use different levels of post processing -- the player performs that post processing on the video after it's been read during decoding & before display. Many DVD players could play DivX video but the level of post processing that they could handle varied, so you had different levels of DivX files, & some, not all could be played by some, not all DVD players. Now that they've moved to AVC, the older, lower level DivX is still around, and still for the most part interchangeable with Xvid. Many of the converters on GOTD offer an option of DivX which was/is only Xvid under a DivX label

   I don't know what to say re: "Alternative". Earlier Windows Media & DivX & Nero Digital & Real etc. were mpeg4 codecs that offered similar levels of compression & quality. You used one or you chose to use another. http://www.merriam-webster.com/dictionary/alternative

   "4. AVI is not a codec, it’s a container. You can put any codec (Cinepak, …) inside an AVI file. In this case, VirtualDub may not be able to open it, especially if it contains VBR audio."

   Yes, an avi file is a container, though many formats are unsupported, & many are frowned upon because they just don't work well. The original comment that started all this was someone suggesting that they could use whatever converter to get an avi file that V/Dub would import. That implies Xvid more than it implies Avid. Generally you should avoid that unneeded conversion -- that's why there's Avisynth -- but if you must make sure you can use a good, modern, [near] lossless codec.

   Posted 10 years ago #

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