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• h.264 lossless video in python with ffmpeg

  7 mars 2015, par Ojtwist

  I have raw video files which I encoded via ffmpeg (lossless) :

  ffmpeg -i test.avi -c:v libx264 -preset veryslow -crf 0 output.mkv

  Now I tried to read these in python :

      FFMPEG_BIN = "ffmpeg"
  
  
  
      command = [FFMPEG_BIN,
  
                     '-i',path,
  
                     '-f', 'image2pipe',
  
                     '-pix_fmt','yuv444p',
  
                     '-r',framerate,
  
                     '-ss',startposition,
  
                     '-vcodec','rawvideo','-']
  
  
  
      pipe = sp.Popen(command,stdout=sp.PIPE,bufsize=10**8)
  
  
  
      while True:
  
          raw_image = pipe.stdout.read(640*480*3)
  
  
  
          image = np.fromstring(raw_image,dtype='uint8')
  
  
  
          image = image.reshape((480,640,3))

  I can’t find the good command to get the video lossless in python. If I try it as mentioned above and show it with matplotlib, I get :
  

  If I set -vcodec to libx264 I get noise.

  

  If i set -pix_fmt to rgb24, I get a normal looking image, but I can see some artifact due to the color conversion.

  What is the command I am looking for ?

  ---

  extra info, the output of the encoding (initial raw video ==> lossless h.264) :

  worker@worklati:~/data/DMG/test$ ffmpeg -i test.avi -c:v libx264 -preset veryslow -crf 0 output.mkv
  
  ffmpeg version 2.5.3 Copyright (c) 2000-2015 the FFmpeg developers
  
    built on Jan 11 2015 17:53:45 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
  
    configuration: --extra-libs=-ldl --prefix=/opt/ffmpeg --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-libpulse --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame --enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr --enable-libxvid --enable-libvo-aacenc --enable-libvidstab
  
    libavutil      54. 15.100 / 54. 15.100
  
    libavcodec     56. 13.100 / 56. 13.100
  
    libavformat    56. 15.102 / 56. 15.102
  
    libavdevice    56.  3.100 / 56.  3.100
  
    libavfilter     5.  2.103 /  5.  2.103
  
    libavresample   2.  1.  0 /  2.  1.  0
  
    libswscale      3.  1.101 /  3.  1.101
  
    libswresample   1.  1.100 /  1.  1.100
  
    libpostproc    53.  3.100 / 53.  3.100
  
  Input #0, avi, from 'test.avi':
  
    Duration: 00:10:25.17, start: 0.000000, bitrate: 44237 kb/s
  
      Stream #0:0: Video: rawvideo, bgr24, 640x480, 6 fps, 6 tbr, 6 tbn, 6 tbc
  
  File 'output.mkv' already exists. Overwrite ? [y/N] y
  
  No pixel format specified, yuv444p for H.264 encoding chosen.
  
  Use -pix_fmt yuv420p for compatibility with outdated media players.
  
  [libx264 @ 0x1fd7160] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX AVX2 FMA3 LZCNT BMI2
  
  [libx264 @ 0x1fd7160] profile High 4:4:4 Predictive, level 3.2, 4:4:4 8-bit
  
  [libx264 @ 0x1fd7160] 264 - core 142 r2389 956c8d8 - H.264/MPEG-4 AVC codec - Copyleft 2003-2014 - http://www.videolan.org/x264.html - options: cabac=1 ref=16 deblock=1:0:0 analyse=0x3:0x133 me=umh subme=9 psy=0 mixed_ref=1 me_range=24 chroma_me=1 trellis=0 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=0 chroma_qp_offset=0 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=0 weightp=2 keyint=250 keyint_min=6 scenecut=40 intra_refresh=0 rc=cqp mbtree=0 qp=0
  
  Output #0, matroska, to 'output.mkv':
  
    Metadata:
  
      encoder         : Lavf56.15.102
  
      Stream #0:0: Video: h264 (libx264) (H264 / 0x34363248), yuv444p, 640x480, q=-1--1, 6 fps, 1k tbn, 6 tbc
  
      Metadata:
  
        encoder         : Lavc56.13.100 libx264
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
  
  Press [q] to stop, [?] for help
  
  frame= 3751 fps= 40 q=-1.0 Lsize=  133724kB time=00:10:25.16 bitrate=1752.3kbits/s    
  
  video:133691kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.024307%
  
  [libx264 @ 0x1fd7160] frame I:16    Avg QP: 0.00  size: 58298
  
  [libx264 @ 0x1fd7160] frame P:3735  Avg QP: 0.00  size: 36403
  
  [libx264 @ 0x1fd7160] mb I  I16..4: 65.3%  6.9% 27.7%
  
  [libx264 @ 0x1fd7160] mb P  I16..4:  3.0%  2.1%  0.2%  P16..4: 71.2%  0.8% 22.4%  0.0%  0.0%    skip: 0.1%
  
  [libx264 @ 0x1fd7160] 8x8 transform intra:36.9% inter:49.5%
  
  [libx264 @ 0x1fd7160] coded y,u,v intra: 79.3% 0.0% 0.0% inter: 97.6% 0.0% 0.0%
  
  [libx264 @ 0x1fd7160] i16 v,h,dc,p: 20%  3% 76%  1%
  
  [libx264 @ 0x1fd7160] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu:  5%  8% 80%  1%  1%  2%  1%  1%  1%
  
  [libx264 @ 0x1fd7160] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 23% 28% 16%  5%  7%  8%  5%  4%  5%
  
  [libx264 @ 0x1fd7160] Weighted P-Frames: Y:0.2% UV:0.0%
  
  [libx264 @ 0x1fd7160] ref P L0: 63.2%  0.0% 14.2%  5.3%  4.0%  3.2%  2.6%  1.1%  1.0%  1.0%  0.9%  1.1%  0.7%  0.6%  0.6%  0.6%
  
  [libx264 @ 0x1fd7160] kb/s:1751.85

• Running Windows XP In 2016

  2 janvier 2016, par Multimedia Mike

  I have an interest in getting a 32-bit Windows XP machine up and running. I have a really good yet slightly dated and discarded computer that seemed like a good candidate for dedicating to this task. So the question is : Can Windows XP still be installed from scratch on a computer, activated, and used in 2016 ? I wasn’t quite sure since I have heard stories about how Microsoft has formally ended support for Windows XP as of the first half of 2014 and I wasn’t entirely sure what that meant.

  Spoiler : It’s still possible to install and activate Windows XP as of the writing of this post. It’s also possible to download and install all the updates published up until support ended.

  The Candidate Computer
  This computer was assembled either in late 2008 or early 2009. It was a beast at the time.

  
  
  Click for a larger image
  

  It was built around the newly-released NVIDIA GTX 280 video card. The case is a Thermaltake DH-101, which is a home theater PC thing. The motherboard is an Asus P5N32-SLI Premium with a Core 2 Duo X6800 2.93 GHz CPU on board. 2 GB of RAM and a 1.5 TB hard drive are also present.

  The original owner handed it off to me because their family didn’t have much use for it anymore (too many other machines in the house). Plus it was really, obnoxiously loud. The noisy culprit was the stock blue fan that came packaged with the Intel processor (seen in the photo) whining at around 65 dB. I replaced the fan and brought the noise level way down.

  As for connectivity, the motherboard has dual gigabit NICs (of 2 different chipsets for some reason) and onboard wireless 802.11g. I couldn’t make the latter work and this project was taking place a significant distance from my wired network. Instead, I connected a USB 802.11ac dongle and antenna which is advertised to work in both Windows XP and Linux. It works great under Windows XP. Meanwhile, making the adapter work under Linux provided a retro-computing adventure in which I had to modify C code to make the driver work.

  So, score 1 for Windows XP over Linux here.

  The Simple Joy of Retro-computing
  One thing you have to watch out for when you get into retro-computing is fighting the urge to rant about the good old days of computing. Most long-time computer users have a good understanding of the frustration that computers keep getting faster by orders of magnitude and yet using them somehow feels slower and slower over successive software generations.
  

  This really hits home when you get old software running, especially on high-end hardware (relative to what was standard contemporary hardware). After I got this new Windows XP machine running, as usual, I was left wondering why software was so much faster a few generations ago.

  Of course, as mentioned, it helps when you get to run old software on hardware that would have been unthinkably high end at the software’s release. Apparently, the minimum WinXP specs as set by MS are a 233 MHz Pentium CPU and 64 MB of RAM, with 1.5 GB of hard drive space. This machine has more than 10x the clock speed (and 2 CPUs), 32x the RAM, and 1000x the HD space. Further, I’m pretty sure 100 Mbit ethernet was the standard consumer gear in 2001 while 802.11b wireless was gaining traction. The 802.11ac adapter makes networking quite pleasant.

  Purpose
  Retro-computing really seems to be ramping up in popularity lately. For some reason, I feel compelled to declare at this juncture that I was into it before it was cool.

  Why am I doing this ? I have a huge collection of old DOS/Windows computer games. I also have this nerdy obsession with documenting old video games in the MobyGames database. I used to do a lot of this a few years ago, tracking the effort on my gaming blog. In the intervening years, I have still collected a lot of old, unused, unloved video games, usually either free or very cheap while documenting my collection efforts on that same blog.

  So I want to work my way through some of this backlog, particularly the games that are not yet represented in the MobyGames database, and even more pressing, ones that the internet (viewed through Google at least) does not seem to know about. To that end, I thought this was a good excuse to get Windows XP on this old machine. A 32-bit Windows XP machine is capable of running any software advertised as supporting Windows XP, Windows ME, Windows 98, Windows 95, and even 16-bit Windows 3.x (I have games for all these systems). That covers a significant chunk of PC history. It can probably be made to run DOS games as well, but those are (usually) better run under DosBox. In order to get the right display feel, I even invested in a (used) monitor sporting a 4:3 aspect ratio. If I know these old games, most will be engineered and optimized for that ratio rather than the widescreen resolutions seen nowadays.

  I would also like to get back to that Xbox optical disc experimentation I was working on a few years ago. Another nice feature of this motherboard is that it still provides a 40-pin IDE/PATA adapter which makes the machine useful for continuing that old investigation (and explains why I have that long IDE cable to no where pictured hanging off the board).

  The Messy Details
  I did the entire installation process twice. The first time was a bumbling journey of discovery and copious note-taking. I still have Windows XP installation media that includes service pack 2 (SP2), along with 2 separate licenses that haven’t been activated for a long time. My plan was to install it fresh, then install the relevant drivers. Then I would investigate the Windows update and activation issues and everything should be fine.

  So what’s the deal with Windows Update for XP, and with activations ? Second item first : it IS possible to still activate Windows XP. The servers are still alive and respond quickly. However, as always, you don’t activate until you’re sure everything is working at some baseline. It took awhile to get there.

  As for whether Windows Update still works for XP, that’s a tougher question. Short answer is yes ; longer answer is that it can be difficult to kick off the update process. At least on SP2, the “Windows Update” program launches IE6 and navigates to a special microsoft.com URL which initiates the update process (starting with an ActiveX control). This URL no longer exists.

  From what I can piece together from my notes, this seems to be the route I eventually took :

  1. Install Windows XP fresh
  2. Install drivers for the hardware ; fortunately, Asus still has all the latest drivers necessary for the motherboard and its components but it’s necessary to download these from another network-connected PC since the networking probably won’t be running “out of the box”
  3. Download the .NET 3.5 runtime, which is the last one supported by Windows XP, and install it
  4. Download the latest NVIDIA drivers ; this needs to be done after the previous step because the installer requires the .NET runtime ; run the driver installer and don’t try to understand why it insists on re-downloading .NET 3.5 runtime before installation
  5. While you’re downloading stuff on other computers to be transported to this new machine, be sure to download either Chrome or Firefox per your preference ; if you try to download via IE6, you may find that their download pages aren’t compatible with IE6
  6. Somewhere along the line (I’m guessing as a side effect of the .NET 3.5 installation), the proper, non-IE6-based Windows Update program magically springs to life ; once this happens, there will be 144 updates (in my case anyway) ; installing these will probably require multiple reboots, but SP3 and all known pre-deprecation security fixes will be installed
  7. Expect that, even after installing all of these, a few more updates will appear ; eventually, you’ll be at the end of the update road
  8. Once you’re satisfied everything is working satisfactorily, take the plunge and activate your installation

  Residual Quirks
  Steam runs great on Windows XP, as do numerous games I have purchased through the service. So that opens up a whole bunch more games that I could play on this machine. Steam’s installer highlights a curious legacy problem of Windows XP– it seems there are many languages that it does not support “out of the box” :

  
  
  

  It looks like the Chinese options and a few others that are standard now weren’t standard 15 years ago.

  Also, a little while after booting up, I’ll get a crashing error concerning a process called geoforms.scr. This appears to be NVIDIA-related. However, I don’t notice anything obviously operationally wrong with the system.

  Regarding DirectX support, DirectX 9 is the highest version officially supported by Windows XP. There are allegedly methods to get DirectX 10 running as well, but I don’t care that much. I did care, briefly, when I realized that a bunch of the demos for the NVIDIA GTX 280 required DX10 which left me wondering why it was possible to install them on Windows XP.

  Eventually, by installing enough of these old games, I fully expect to have numerous versions of .NET, DirectX, QT, and Video for Windows installed side by side.

  Out of curiosity, I tried playing a YouTube HD/1080p video. I wanted to see if the video was accelerated through my card. The video played at full speed but I noticed some tearing. Then I inspected the CPU usage and noticed that the CPU was quite loaded. So either the GTX 280 doesn’t have video acceleration, or Windows XP doesn’t provide the right APIs, or Chrome is not able to access the APIs in Windows XP, or perhaps some combination of the foregoing.

  Games are working well, though. I tried one of my favorite casual games and got sucked into that for, like, an entire night because that’s what casual games do. But then, I booted up a copy of WarCraft III that I procured sometime ago. I don’t have any experience with the WarCraft universe (RTS or MMO) but I developed a keen interest in StarCraft II over the past few years and wanted to try WarCraft III. Unfortunately, I couldn’t get WarCraft III to work correctly on several different Windows 7 installations (movies didn’t play, which left me slightly confused as to what I was supposed to do).

  Still works beautifully on the new old Windows XP machine.

  The post Running Windows XP In 2016 first appeared on Breaking Eggs And Making Omelettes.

• How Media Analytics for Piwik gives you the insights you need to measure how effective your video and audio marketing is – Part 1

  31 janvier 2017, par InnoCraft — Community

  Do you have video or audio content on your website or in your app ? If you answered this with yes, you should continue reading and learn everything about our Media Analytics premium feature.

  When you produce video or audio content, you are either spending money or time or often both money and time on your content in the hope of increasing conversions or sales. This means you have to know how your media is being used, when it is used, for how long and by whom. You can simply not afford not to know how this content affects your overall business goals as you are likely losing money and time by not making the most out of it. Would you be able to answer any of the above questions ? Do you know whether you can justify the cost and time for producing them, which videos work better than others and how they support your marketing strategy ? Luckily, getting all these insights is now so trivial it is almost a crime to not measure it.

  Getting Media Analytics and Installation

  Media Analytics can be purchased from the Piwik Marketplace where you find all sorts of free plugins as well as several premium features such as A/B Testing or Funnel. After the purchase you will receive a license key that you can enter in your Piwik to install and update the plugin with just one click.

  The feature will in most cases automatically start tracking your media content and you don’t even need to change the tracking code on your website. Currently supported players are for example YouTube, Vimeo, HTML 5, JW Player, VideoJS and many more players. You can also easily extend it by adding a custom media player or simply by letting us know which player you use and we will add support for it for you.

  By activating this feature, you get more than 15 new media reports, even more exportable widgets, new segments, APIs, and more. We will cover some of those features in this blog post and in part 2. For a full list of features check out the Media Analytics page on the Piwik Marketplace.

  Media Overview

  As the name says, it gives you an overview over your media usage and how it performs over time. You can choose any media metrics in the big evolution graph and the sparklines below give you an overview over all important metrics in a glance.

  

  It lets you for example see how often media was shown to your users, how often users start playing your media, for how long they watched it, how often they finished it, and more. If you see some spikes there, you should definitely have a deeper look at the other reports. When you hover a metric, it will show you a tooltip explaining how the data for this is collected and what it means.

  Real-Time Media

  On the Real-Time page you can see how your content is being used by your visitors right now, for example within the last 30 minutes, last 60 minutes and last 24 hours.

  It shows you how many plays you had in the last minutes, for how long they played it, and it shows you currently most popular media titles. This is great to discover which media content performs best right now and lets you make decisions based on user behaviour that is happening right now.

  

  Below you can see our Audience Real-Time Map that shows you from where in the world your media is being played. A bigger circle indicates that a media play happened more recently and of course you can zoom in down to countries and regions.

  

  All the reports update every few seconds so you can always have a look at it and see in just a second how your content is doing and how certain marketing campaigns affect it. All these real-time reports can be also added as widgets to any of your Piwik Dashboards and they can be exported for example as an iframe.

  Video, Audio and Media Player reports

  Those reports come with so many features, we need a separate blog post and cover this in part 2.

  Events

  Media Analytics will automatically track events so you can see how often users pressed for example play or pause, how often they resumed a video and how often they finished a video. This helps you better understand how your media is being used.

  

  For example in the past we noticed a couple of videos with lots of pause and resume events. We then had a look at the Audience Log – which we will cover next – to better understand why visitors paused the videos so often. We then realized they did this especially for videos that were served from a specific server and because the videos were loading so slow, users often pressed pause to let the media buffer, then played the media for a few seconds and then paused it again as they had to wait for the video to load. Moving those videos to another, faster server showed us immediate results in the number of pauses going down and on average visitors watched the videos for much longer.

  Audience Log

  At InnoCraft, we understand that not only aggregated metrics matter but also that you often need the ability to dig into your data and “debug” certain behaviours to understand the cause for some unusual high or low metrics. For example you may find out that many of your users often pause a video, then you wonder how each individual user behaved so you can better understand the why.

  

  The audience log shows you a detailed log of every visitor. You can chronologically see every action a visitor has performed during their whole visit. If you click on the visitor profile link, you can even see all visits of a specific visitor, and all actions they have ever performed on your website.

  This lets you ultimately debug and understand your visitors and see exactly which actions they performed before playing your media, which media they played, how they played your media, and how they behaved after playing your media.

  The visitor log of course also shows important information about each visitor like where they came from (referrer), their location, software, device and much more information.

  Audience Map

  The Audience Map is similar to the Real-Time Map but it shows you the locations of your visitors based on a selected date range and not in real time. The darker the blue, the more visitors from that country, region or city have interacted with your media.

  

  Coming in part 2

  In the next part we will cover which video, audio and media player reports Media Analytics provides, how segmenting gives you insights into different personas, and how nicely it integrates into Piwik.

  How to get Media Analytics and related features

  You can get Media Analytics on the Piwik Marketplace. If you want to learn more about this feature, you might be also interested in the Media Analytics User Guide and the Media Analytics FAQ.