How can I convert swf files to mp4 now on Windows?

Using JPEXS Free Flash Decompiler (FFDec) combined with a custom script is a powerful method to convert SWF to MP4, but it is not a straightforward one-step conversion if as a SWF to MP4 software . FFDec is primarily a tool for extracting and analyzing resources from SWF files, not a video converter.

To achieve a true MP4 output, you would need to create a two-step workflow using a script to automate the process.

1. Export Video and Audio Separately: Use FFDec's command-line interface to export the video stream and the audio from the SWF file. The FrameExporter can handle animation frames, while the Sound Exporter handles audio extraction.

2. Combine and Convert with Another Tool: You would then need to use a second tool, like FF mpeg, in your script to combine the exported video and audio streams into a single MP4 file.

A script for this process might look something like this:

bash

# Step 1: Export video frames as FLV

java -jar ffdec.jar -export frame -format flv your_file. swf ./output/

# Step 2: Export audio as MP3

java -jar ffdec.jar -export sound -format mp3 your_file. swf ./output/

# Step 3: Combine and convert to MP4 using FF mpeg

ffm peg -i ./output/frame_0.flv -i ./output/sound_0.mp3 -c:v copy -c:a aac output_video. mp4

While you can create a script that uses JPEXS and FF mpeg to achieve the conversion, you would be using JP EXS to extract data and another tool to build the final MP4. This method is a "challenging and complex free method" that avoids dedicated SWF to MP4 software, but it comes with significant technical hurdles.