Answers.Body: <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>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-04-17T09:00:28.453Z
Answers.Text: Thank you! I appreciate this.
Answers.UserDisplayName: murage kibicho
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-04-17T09:47:56.253Z
Answers.Text: Yes, it's rapid assessment on a mobile device. My target video consumer would be anyone watching a video on a mobile phone.
Answers.UserDisplayName: murage kibicho
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-04-17T04:49:26.677Z
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Body: <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>
  
Tags: <ffmpeg><video-quality><h.264><h.265>
Title: Idea validation - CRF's as a service
UserDisplayName: murage kibicho
ThreadText: # 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
  
  
  ---
  
  ## 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.  
  
  ---
  
  