<p>I assume you want to identify the CRF value that will either achieve a target file size or a target score on a quality metric like PSNR or VMAF.
However, a single frame is not enough to assess that.</p>
<p>The obtained average bit rate for a CRF encode of a file depends on the visual texture complexity and motion within <em>each scene</em>. So, you would need to process a set of representative range of frames from each scene. That doesn't fit with your proposal which appears to be a rapid assessment tool that looks at one frame (on a mobile device?).</p>
<p>There is an appreciable need for such a service, but it would run on the final encoding machine and examine the whole file, so probably a piece of software or script.</p>

CC BY-SA 4.0
2022-04-17T09:00:28.453Z
Thank you! I appreciate this.
murage kibicho
CC BY-SA 4.0
2022-04-17T09:47:56.253Z
Yes, it's rapid assessment on a mobile device. My target video consumer would be anyone watching a video on a mobile phone.
murage kibicho
CC BY-SA 4.0
2022-04-17T04:49:26.677Z
2022-04-17T04:49:26.677Z
Gyan
<p>I was looking for validation for my startup idea. Please flag if this is off-topic.</p>
<p><strong>Idea:</strong> CRF's as a service - When encoding h.264 and libvpx videos, I tend to guess good Constant Rate Factors(CRF's) to make my videos smaller. I bet you guys experience the same. Instead of guessing, why not send the video to a dedicated 'crf-finder' then encode it later? The &quot;crf-finder&quot; would take a single video frame and find the best crf value.</p>
<p><strong>Questions</strong></p>
<ol>
<li>Do you think this is dumb?</li>
<li>How much would you pay for this?
This is my <a href="https://phoneworker.online/" rel="nofollow noreferrer">landing page</a>. Perhaps you could look at it, subscribe to my mailing list or even try it out. I'm not charging - only trying to figure out if this is useful.</li>
</ol>
<p><strong>This is what crf-finding looks like</strong>
<a href="https://i.sstatic.net/L0RxP.gif" rel="nofollow noreferrer"><img src="https://i.sstatic.net/L0RxP.gif" alt="phoneworker finding a crf" /></a></p>

<ffmpeg><video-quality><h.264><h.265>
Idea validation - CRF's as a service
murage kibicho
# Idea validation - CRF's as a service

(Asked by: username_0 on 2022-04-16)

I was looking for validation for my startup idea. Please flag if this is off-topic.

**Idea:** CRF's as a service - When encoding h.264 and libvpx videos, I tend to guess good Constant Rate Factors(CRF's) to make my videos smaller. I bet you guys experience the same. Instead of guessing, why not send the video to a dedicated 'crf-finder' then encode it later? The "crf-finder" would take a single video frame and find the best crf value.

**Questions**

1. Do you think this is dumb?
2. How much would you pay for this?
   This is my [landing page](https://phoneworker.online/). Perhaps you could look at it, subscribe to my mailing list or even try it out. I'm not charging - only trying to figure out if this is useful.

**This is what crf-finding looks like**
[![phoneworker finding a crf](https://i.sstatic.net/L0RxP.gif)](https://i.sstatic.net/L0RxP.gif)

**Tags:** ffmpeg, video-quality, h.264, h.265


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## 1 answers

### Answer by username_1 on 2022-04-17. Score: 1 | Accepted answer

I assume you want to identify the CRF value that will either achieve a target file size or a target score on a quality metric like PSNR or VMAF.
However, a single frame is not enough to assess that.

The obtained average bit rate for a CRF encode of a file depends on the visual texture complexity and motion within *each scene*. So, you would need to process a set of representative range of frames from each scene. That doesn't fit with your proposal which appears to be a rapid assessment tool that looks at one frame (on a mobile device?).

There is an appreciable need for such a service, but it would run on the final encoding machine and examine the whole file, so probably a piece of software or script.

> **Comments:**
> **username_0**: Thank you! I appreciate this.  
> **username_0**: Yes, it's rapid assessment on a mobile device. My target video consumer would be anyone watching a video on a mobile phone.  

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