i have lots of downloaded... ISOs... that i need to converto to save space. I would like to make them all of the same size, let's say 720p, and same format, let's say h265.
I am on linux and the... ISOs... are sorted into a neatly named hierarchy of sub-folderds, which i want to preserve too. What is the best tool (CLI) for the scope? I can use ffmpeg with a bash script, but is there anything better suited?
I compared a bunch of crf values, taking video quality, encode time and file size into account on a few episodes from some of my favorite shows and ended up settling on this.
For the most part, I don't notice a quality difference compared to my source, but it might just be because of my bad eyes or my monitor lol. But I did notice quality differences around 35 + so they were out.
At crf 0 I'm encoding a 40 min epsisode in about 5 mins which I'm happy with, I probably could have saved time going for a higher value but most of the time I run the script when I'm sleeping so time wasn't a big issue as long as it wasn't taking 20+ mins to encode 1 file
Going for 0 meant I'd have as close to the same quality as my source, using the default preset, and I didn't notice huge file size differences between 0 and 30.
I've encoded pretty much all of my TV shows now and I've dropped the size of my TV directory to about 1/4 of the original size so going for a higher crf value didn't seem worth it to me, if I had noticed that my file size at crf 5 was half what it is at crf 0 then I would probably have went with crf 5
I think its pretty subjective some people are happy with 720p and others won't settle for less than 4k so I don't think this would be a great solution for everyone to do but I think people should play around with different parameters to see what works best for them.
I'm pretty certain the two options I can think of are just front-ends for ffmpeg: Handbrake and Tdarr, Tdarr runs as a service and monitors your folder for things that don't match spec and then converts them, if you plan to continue acquiring ISOs.
Tdarr looks great, but I don't love Foss software which have paid plans attached. Can it be used really for free if I have one server and plan to do all transcoding there?
Yes. I believe the paid version only gives you more possible nodes (where the transcoding is done), and more reports? But yes, you have the entire suite of tools necessary in the free version. It's worked great for me, I've used it for a year and a half now
Great point about paid plans. I didn't look closely at the project today - they didn't have any paid plans when I was first trying it in 2020 (and ultimately decided downloading the preferred source was good enough and abandoned trans-coding).
This is a more script based solution I've tried in the past for ongoing ISOs with decent results. Good luck!
My internet speed doesn't allow for this unfortunately. On Usenet I can reach 1mb/sec when lucky. And 6Tb of stuff takes time to find and download again.
I had the same need and didn’t want to read tooo much about ffmpeg and its options. I ended up using fastflix which uses ffmpeg under the hood with built in presets. Supports queues and lots of more stuff.
Usually it's not worth it. Redownload your videos in the desired size. Use radarr et al to manage it.
There are People who are specialized on the task.only use raw material to encode. Reencoding makes quality worse. And time and effort isn't worth it.
It's much cheaper to buy more drives than to reencode a large library to av1 in order to save space.
For batch converting ISOs to a specific resolution and format while preserving folder hierarchy on Linux, you can indeed use ffmpeg with a bash script. However, you might also consider using HandBrakeCLI, which is a command-line interface for HandBrake, a popular video transcoder.
Here's how you could use HandBrakeCLI to achieve your goal:
Install HandBrakeCLI if you haven't already:
sudo apt-get install handbrake-cli
Write a bash script to iterate through your directories, converting ISO files:
#!/bin/bash
# Set input and output directories
input_dir="/path/to/your/input/directory"
output_dir="/path/to/your/output/directory"
# Convert ISOs to 720p h.265
find "$input_dir" -name "*.iso" -type f | while read -r file; do
output_file="${file%.iso}.mp4"
handbrakecli --input "$file" --output "$output_dir/$output_file" --preset="Super HQ 720p30 Surround"
done
Adjust the preset according to your needs. You can check available presets with HandBrakeCLI --preset-list.
Make the script executable:
chmod +x convert_iso.sh
Run the script:
./convert_iso.sh
This script will convert all ISO files in the specified input directory to 720p h.265 MP4 files using HandBrakeCLI while preserving the folder hierarchy.