most recent 30 from video.stackexchange.com 2025-08-07T23:36:42Z https://video.stackexchange.com/feeds/tag/av1+ffmpeg https://creativecommons.org/licenses/by-sa/4.0/rdf https://video.stackexchange.com/q/37243 0 MyPreciousss https://video.stackexchange.com/users/12781 2025-08-07T00:34:34Z 2025-08-07T11:04:35Z

<p>I want to make a video using a cover image and an audio file with the audio file as the length. What's the most optimal modern way to do this with new codecs and high resolutions?</p> <p>Reason why I want 4K/8K: The deployment display is an 8K panel and a lower resolution yields sub-par experience.</p> <p>Here's the command I tried: <code>ffmpeg -r 0.01 -loop 1 -i image.jpg -i audio.mp3 -c:v hevc_toolbox -c:a aac -b:a 196k -pix_fmt yuv420p -shortest out.mp4</code></p> <p>But the output was inconsistent and usually 1.5-2x the length of the audio file even with <code>-shortest</code></p> <p>Relevant Past Research:</p> <ol start="0"> <li><p>ffmpeg has a long-standing still-open bug about this issue where it can't approximate timing of the output correctly: trac.ffmpeg.org/ticket/5456</p> </li> <li><p><a href="https://superuser.com/questions/1041816/combine-one-image-one-audio-file-to-make-one-video-using-ffmpeg">https://superuser.com/questions/1041816/combine-one-image-one-audio-file-to-make-one-video-using-ffmpeg</a> but it doesn't cover it</p> </li> </ol> <p>And a lot of Reddit posts with h264/1080p instructions that were not fully applicable here.</p> <blockquote> <p>ffmpeg version 6.1.1 Copyright (c) 2000-2023 the FFmpeg developers built with Apple clang version 15.0.0 (clang-1500.1.0.2.5)</p> </blockquote>

https://video.stackexchange.com/q/38006 1 Satyam Manoj Singh https://video.stackexchange.com/users/50185 2025-08-07T08:21:03Z 2025-08-07T18:59:06Z

<p>I'm implementing a video transcoding pipeline using FFmpeg with the libsvtav1 encoder to convert H.264 videos to AV1. However, I'm seeing unexpected results: the output files are larger than the originals, even when using CRF values (24 and 30) that should theoretically reduce file size.</p> <p>Current Implementation:</p> <pre><code># Attempt 1 ffmpeg -i input.mp4 -c:v libsvtav1 -crf 24 -y output_crf24.mp4 # Attempt 2 ffmpeg -i input.mp4 -c:v libsvtav1 -crf 30 -y output_crf30.mp4 </code></pre> <p>Example Input vs Output: Original H.264 (input.mp4):</p> <p>Resolution: 1280x960</p> <p>Bitrate: ~1463 kb/s</p> <p>Codec info (via ffprobe):</p> <pre><code>Stream #0:0: Video: h264 (High), yuv420p(progressive), 1280x960, 1460 kb/s, 30 fps AV1 Encoded Output (CRF 24): </code></pre> <p>Bitrate: ~1503 kb/s</p> <p>Codec info:</p> <pre><code>Stream #0:0: Video: av1 (Main), yuv420p, 1280x960, 1501 kb/s, 30 fps encoder: Lavc62.0.101 libsvtav1 </code></pre> <p>What I've Tried: Varying CRF values: 24 and 30</p> <p>Using FFmpeg’s default preset settings (no additional tuning or options)</p>

https://video.stackexchange.com/q/37796 2 EllipticalInitial https://video.stackexchange.com/users/25617 2025-08-07T22:44:53Z 2025-08-07T22:44:53Z

<p>I'm encoding 16 bpc PNG sequences into various lossy video formats for archival purposes because the file sizes are so big. I'm only considering codecs which support 444 and at least 10 bit color. Right now the best I've found seem to be HEVC and AV1. In ffmpeg, they both support the <code>yuv444p12le</code> pixel format, which is great. However, I need help tuning the encode parameters to try and balance the the following as best as possible:</p> <ul> <li>Maximize the minimum quality of any given frame of the animation</li> <li>Keep the filesize relatively low.</li> </ul> <p>Right now with AV1 I'm finding that the PSNR per frame tends to be a lot &quot;spikier&quot; than HEVC; and I don't know why. I attached an image as an example, where the blue line is the PSNR over each frame when encoding with AV1 while the pink is with HEVC.</p> <p><a href="https://i.sstatic.net/82yJ2eQT.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/82yJ2eQT.png" alt="enter image description here" /></a></p> <p>The SSIM is similar, but not as bad:</p> <p><a href="https://i.sstatic.net/OlPHezt1.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/OlPHezt1.png" alt="enter image description here" /></a></p> <p>The exact commands used to encode each are included below:</p> <p>AV1:</p> <p><code>ffmpeg -framerate 60 -i &quot;input%04d.png&quot; -y -pix_fmt yuv444p12le -c:v libaom-av1 -crf 15 -b:v 500M -cpu-used 1 -row-mt 1 -tiles 2x2 output.mkv</code></p> <p>HEVC:</p> <p><code>ffmpeg -framerate 60 -i &quot;input%04d.png&quot; -y -c:v libx265 -preset veryslow -crf 9 -pix_fmt yuv444p12le &quot;output.mp4&quot;</code></p> <p>I don't like how there are big dips in the AV1 PSNR occurring repeatedly (the spikes downward in the blue line on the PSNR plot), since it means there are big differences from one frame to the next, even if the overall average PSNR level is pretty high. I'd prefer to make it smoother if possible.</p> <p>It doesn't seem to be an issue with HEVC.</p> <p>Do you have suggestions for changes I can make to my AV1 encoding command which will prevent those spikes? If so, can you also explain why those changes will help?</p>

https://video.stackexchange.com/q/37149 0 Shanoa Ice https://video.stackexchange.com/users/43467 2025-08-07T05:52:47Z 2025-08-07T10:11:44Z

<p>Since I heard librav1e is kind of the fastest AV1 software encoder, I attempted to use it to convert an old MPEG-4 Visual video to AV1, but the result is way slower than the popular SVT-AV1 encoder. When I was using the default preset and a vbr of ~1200kbps of SVT-AV1 I can get an about 110 fps speed for that video, but when I use librav1e it barely exceeds 8fps, even with <code>--speed 10</code>. Manually setting thread count or ramping up tiles does not work either. When I examine closely I see my CPU usage is normally 100% all the time with SVT-AV1, but with rav1e I only get about 30%~40% CPU Utilization.</p> <p>I have confirmed that rav1e is using AVX2 by piping YUV output to a natively-built rav1e, both on Windows and Linux, so now I am quite puzzled by the situation: why does rav1e failed to pump out the full potential of my machine?</p> <p>For a bit more context I am using a gaming laptop with 5800H CPU.</p>

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