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• How to Use SVG Image Files Directly in FFmpeg ? [closed]

  10 mars, par Pubg Mobile

  I generated a bar chart race using the Flourish Studio website and captured the frames as a PDF sequence using a Python Playwright script. Then, I converted all the PDF files into SVG format using the following Python script, because SVG is the only image format that maintains quality without loss when zoomed in :

  


  import os
import subprocess
import multiprocessing

# Define paths
pdf2svg_path = r"E:\Desktop\dist-64bits\pdf2svg.exe"  # Full path to pdf2svg.exe
input_dir = r"E:\Desktop\New folder (4)\New folder"
output_dir = r"E:\Desktop\New folder (4)\New folder (2)"

# Ensure output directory exists
os.makedirs(output_dir, exist_ok=True)

def convert_pdf_to_svg(pdf_file):
    """ Convert a single PDF file to SVG. """
    input_pdf = os.path.join(input_dir, pdf_file)
    output_svg = os.path.join(output_dir, os.path.splitext(pdf_file)[0] + ".svg")

    try:
        subprocess.run([pdf2svg_path, input_pdf, output_svg], check=True)
        print(f"Converted: {pdf_file} -> {output_svg}")
    except FileNotFoundError:
        print(f"Error: Could not find {pdf2svg_path}. Make sure the path is correct.")
    except subprocess.CalledProcessError:
        print(f"Error: Conversion failed for {pdf_file}")

if __name__ == "__main__":
    # Get list of PDF files in input directory
    pdf_files = [f for f in os.listdir(input_dir) if f.lower().endswith(".pdf")]

    # Use multiprocessing to speed up conversion
    with multiprocessing.Pool(processes=multiprocessing.cpu_count()) as pool:
        pool.map(convert_pdf_to_svg, pdf_files)

    print("All conversions completed!")


  


  Problem :

  


  Now, I want to use these SVG images in FFmpeg to create a high-quality video file. However, FFmpeg does not support SVG files directly, and I have read that I must convert SVG files into PNG before using them in FFmpeg. The problem is that PNG images reduce quality, especially when zooming in, which is why I want to avoid converting to PNG.

  


  Is there any way to use SVG files directly in FFmpeg or another method to convert them into a high-quality video while maintaining full resolution ? Any ideas or suggestions would be greatly appreciated !

  


• App engine php flex env exec("ffmpeg...") - Unable to open logfile : /dev/stderr

  15 octobre 2018, par dan

  I’m trying to run FFMPEG on the app engine flex env for php.

  I’ve whitelisted the exec() function in my app.yaml and installed FFMPEG using the docker file - so far so good.

  When I’m running a exec("usr/bin/ffmpeg [args]...") I get an error that ffmpeg can’t access the dev/stderr and the function shuts down. see ref :

  WARNING : [pool app] child 44 said into stderr : "NOTICE : PHP message : ALERT - Unable to open logfile : /dev/stderr (attacker ’’, file ’/app/index.php’, line 49)"

  WARNING : [pool app] child 44 said into stderr : "NOTICE : PHP message : PHP Warning : exec() has been disabled for security reasons in /app/index.php on line 49"

  My configuration files are as follows :

  APP.YAML :

  runtime: custom
  
  env: flex
  
  runtime_config:
  
    document_root: .

  COMPOSER.JSON :

  {
  
      "require": {
  
          "php": "5.6.*",
  
          "google/cloud-storage": "^1.0",
  
      }
  
  }

  DOCKERFILE :

  FROM gcr.io/google-appengine/php:latest
  
  ENV DOCUMENT_ROOT /app
  
  RUN apt-get -y update && apt-get install -y ffmpeg

  INDEX.PHP :

  <?php
  
  //downloaded images into /tmp folder
  
  $cmd = "/usr/bin/ffmpeg -r 24 -i /tmp/frame_%05d.png -r 24 -vcodec libx264 -pix_fmt yuv420p -b 50M -s 1920x1080 -y /tmp/export.mp4";
  
  exec($cmd);
  
  ?>

  I’ve tried using all the other shell function - system(), exec_shell(),proc_open()
  With the same result.

  Any help ?

  Thank you

• ffmpeg 'or' filter - what's the significance of red and blue ?

  9 juillet 2020, par BETLOG

  I'm tinkering with various ffmpeg filters to help me visualise the magnitude of difference certain presets use, and I notice a couple of filters display a lot of certain primary colours.
Specifically in this case : red and blue in an 'or' filter, and green in an 'and' filter.

  


  It seems useful to be able to tell WHICH input is being indicated, or to understand how the filters act in terms of sequence, and I'm hoping these colourations will help with this.
Or at least I'd like to better understand whatever they do represent.

  


  In the screenshot of the video segment above I see pure red and blue occasionally featuring strongly, and as the two extremes in the RgB palette it logically seems (and I'm hoping) they might indicate particular video inputs.
Similarly, the 'and' filter shows a lot of green shades, so I'm hoping someone can explain the meaning of the R,G, and B highlights in the 'or' and the 'and' filters.

  


  The relevant input and preset info in the images below is at the extreme left and right of each drawtext line.