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• NAB 2010 wrapup

  15 avril 2010

  Another year of NAB has come and gone. Making it out of Vegas with some remaining faith in humanity seems like a successful outcome. So, anything worth talking about at the show ?

  First off, there’s 3d. 3D is The Next Big Thing, and that was obvious to anyone who spent half a second on the show floor. Everything from camera rigs, to post production apps, to display technology was all 3d, all the time. I’m not a huge fan of 3d in most cases, but the industry is at least feigning interest.

  Luckily, at a show as big as NAB, there’s plenty of other cool stuff to see. So, what struck my fancy ?

  First off, Avid and Adobe were showing new versions of Media Composer and Premiere. Both sounded pretty amazing on paper, but I must say I was somewhat underwhelmed by both in reality. Premiere felt a little rough around the edges - the Mercurial Engine wasn’t the sort of next generation tech that I expected. Media Composer 5 has some nice new tweaks, but it’s still rather Avid-y - which is good for Avid people, less interesting for the rest of us.

  In other software news, Blackmagic Design was showing off some of what they’re doing with the DaVinci technology that they acquired. Software-only Da Vinci Resolve for $999 is a pretty amazing deal, and the demos were quite nice. That said, color correction is an art, so just making the technology cheaper isn’t necessarily going to dramatically change the number of folks who do it well - see Color.

  Blackmagic also has a pile of new USB 3.0 hardware devices, including the absolutely gorgeous UltraStudio Pro. Makes me pine for USB 3.0 on the mac.

  On the production side, we saw new cameras from just about everyone. To start at the high end, the Arri Alexa was absolutely stunning. Perhaps the nicest digital cinema footage I’ve seen. Not only that, but they’ve worked out a usable workflow, recording to ProRes plus RAW. At the price point they’re promising, the world is going to get a lot more difficult for RED.

  Sony’s new XDCam EX gear is another good step forward for that format. Nothing groundbreaking, but another nice progression. I was kind of hoping we’d see 4:2:2 EX gear from them, but I suppose they need to justify the disc based formats for a while longer.

  The Panasonic AG-AF100 is another interesting camera, bringing micro 4/3rds into video. The only strange thing is the recording side - AVCHD to SD cards. While I’m thrilled to see them using SD instead of P2, it sure would have been nice to have an AVCIntra option.

  Finally, Canon’s 4:2:2 XF cams are a nice option for the ENG/EFP market. Nothing groundbreaking, aside from the extra color sampling, but it’s a nice step up from what they’ve been doing.

  Speaking of Canon, it’s interesting to see the ways that the 5d and 7d have made their way into mainstream filmmaking. At one point, I thought they’d be relegated to the indie community - folks looking for nice DoF on a budget. Instead, they seem to have been adopted by a huge range of productions, from episodic TV to features. While they’re not right for everyone, the price and quality make them an easy choice in many cases.

  One of the stars of the show for me was the GoPro, a small waterproof HD camera that ships with a variety of mounts, designed to be used in places where you couldn’t or wouldn’t use a more full featured camera. No LCD, just a record button and a wide angle lens. I bought two.

  Those are the things that stand out for me. While there was plenty of interesting stuff to be seen, given the current economic conditions at the University, I wasn’t exactly in a shopping mindset. The show definitely felt more optimistic than it did last year, and companies are again pushing out new products. However, attendances was about 20% lower than 2008, and that was definitely noticeable on the show floor.

• Is there a way to use pdf images with the saveVideo function of R's animation package ?

  11 avril 2023, par Hullaballoon

  I've created a few MP4 files using the saveVideo function in the animation package, but the colours are relatively dull in one of them. I've compared the output of one of the images in the animation by producing a PNG and a PDF, with the colours in the PDF appearing much bolder. I was hoping to code the images as PDFs within the animation to see if it improves the output, but I am getting stuck with a message "Rplot.pdf : Invalid data found when processing input" and no MP4 being produced.

  


  The internal code of the saveVideo function implies that PDF images can be used with the following :

  


  num = ifelse(file.ext == "pdf", "", ani.options("imgnfmt"))


  


  Here's a toy example that demonstrates the issue. This works fine :

  


  library(animation)
saveVideo({
  darkcol = "#000000"
  par(bg = darkcol)
  ani.options(interval = 0.5)
  for (i in 1:10)
  {
    plot(0:10, runif(11, 4, 8), col = "magenta1")
    ani.pause()
  }
}, video.name = "TestVideo.mp4",
ani.res = 144, ani.height = 900, ani.width = 1600)


  


  This one doesn't work :

  


  library(animation)
saveVideo({
  pdf(ani.options("img.fmt"))
  darkcol = "#000000"
  par(bg = darkcol)
  ani.options(interval = 0.5)
  for (i in 1:10)
  {
    plot(0:10, runif(11, 4, 8), col = "magenta1")
    ani.pause()
  }
}, video.name = "TestVideoPDF.mp4",
ani.res = 144, ani.height = 9, ani.width = 16,
use.dev = FALSE, ani.type = "pdf")


  


  Here is what the console displays when I run the second batch of code :

  


  Executing: "ffmpeg" -y -framerate 2 -i Rplot.pdf -pix_fmt yuv420p TestVideoPDF.mp4
ffmpeg version 2023-04-06-git-b564ad8eac-full_build-www.gyan.dev Copyright (c) 2000-2023 the FFmpeg developers
built with gcc 12.2.0 (Rev10, Built by MSYS2 project)
configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libaribb24 --enable-libdav1d --enable-libdavs2 --enable-libuavs3d --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libaom --enable-libjxl --enable-libopenjpeg --enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2 --enable-libvpl --enable-libshaderc --enable-vulkan --enable-libplacebo --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libcodec2 --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
libavutil      58.  6.100 / 58.  6.100
libavcodec     60.  9.100 / 60.  9.100
libavformat    60.  4.101 / 60.  4.101
libavdevice    60.  2.100 / 60.  2.100
libavfilter     9.  5.100 /  9.  5.100
libswscale      7.  2.100 /  7.  2.100
libswresample   4. 11.100 /  4. 11.100
libpostproc    57.  2.100 / 57.  2.100
Rplot.pdf: Invalid data found when processing input


  


  I'm on a Windows PC running Windows 10 Enterprise. Any help would be greatly appreciated !

  


• Generating Video from Downloaded Images Using Fluent-FFmpeg : Issue with Multiple Image Inputs

  11 août 2023, par Pratham Bhagat

  I am having trouble creating Video from multiple images using fluent-ffmpeg in node.js.

  


  Here, I am getting the images from rquest body and downloading them in **temp **directory

  


     const imageUrls = req.body.imageUrls;
   const timeInBetween = parseFloat(req.query.time_in_between) || 1.0;

const tempDir = path.join(
      context.executionContext.functionDirectory,
      "temp"
    );

const downloadedImages = await Promise.all(
      imageUrls.map(async (imageUrl, index) => {
        try {
          const response = await axios.get(imageUrl, {
            responseType: "arraybuffer",
          });
          const imageName = `image_${index + 1}.png`;
          const imagePath = path.join(tempDir, imageName);
          await fs.writeFile(imagePath, response.data);
          return imagePath;
        } catch (error) {
          context.log(`Error downloading ${imageUrl}: ${error.message}`);
          return null;
        }
      })
    );


  


  I want to combine these images that are in downloadedImages array and create a video

  


  const outputVideoPath = path.join(tempDir, "output.mp4");

    let ffmpegCommand = ffmpeg();

    for (let i = 0; i < downloadedImages.length; i++) {
      context.log(downloadedImages.length);
      ffmpegCommand
        .input(downloadedImages[i])

        .inputOptions(["-framerate", `1/${timeInBetween}`])
        .inputFormat("image2")
        .videoCodec("libx264")
        .outputOptions(["-pix_fmt", "yuv420p"]);
    }

    ffmpegCommand
      .output(outputVideoPath)
      .on("end", () => {
        context.log("Video generation successful.");
        context.res = {
          status: 200,
          body: "Video generation and cleanup successful.",
        };
      })
      .on("error", (err) => {
        context.log.error("Error generating video:", err.message);
        context.res = {
          status: 500,
          body: "Error generating video: " + err.message,
        };
      })
      .run();


  


  By running it and giving value of "time_in_between" as 2 I get video of 2 seconds with a single image.

  


  

  • Utilized Fluent-FFmpeg library to generate a video from a list of downloaded images.

  


  • Expected the video to include all images, each displayed for a specified duration.

  


  • Tried mapping through the image paths and using chained inputs for each image.

  


  • Expected the video to have a sequence of images displayed.

  


  • Observed that the generated video only contained the first image and was of 0 seconds duration.