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11 of the Most Effective Conversion Rate Optimisation Best Practices
14 février, par ErinDriving more traffic to your website is hard work, but it’s still only half the battle.
You don’t just need to acquire new users ; you need to make sure as many convert as possible to make your digital marketing efforts worthwhile.
That’s why improving your site’s conversion rate is so important. It will also help you get more value from your existing traffic source and keep you in line with your competitors. It’s also probably a lot easier than you think — especially if you adopt optimisation strategies that have been proven to be profitable time and time again.
In this article, we’ll show some of the most powerful, innovative and tried-and-tested conversion rate optimisation strategies you can implement immediately.
What is conversion rate optimisation ?
First, let’s look at what conversion rate optimisation means. Conversion rate optimisation is the practice of improving elements of your website to increase the number of users who take a desired action and turn visitors into customers.
Common conversion goals include :
- Making a purchase
- Adding an item to a shopping cart
- Signing up for a newsletter
- Registering for a free trial
- Downloading an ebook
- Watching a video
It doesn’t matter what your goal is. Using one of the following conversion rate optimisation best practices can send your conversions soaring.
11 conversion rate optimisation best practices
Are you ready to roll up your sleeves and get to work ? Then use one or more of the following best practices to improve your return on investment.
Set a clear goals and hypothesis
When running an A/B or multivariate test, you need a clear idea of what you are testing and why.
A goal (a statement about what you want to achieve) and a hypothesis (a statement about what you expect to happen) clarify the problem you are trying to solve and give you a definitive way to judge the experiment’s results.
Confused ? Just use this template :
We aim to [insert goal] by testing [insert test] on [insert page]. We expect that [insert test] will increase [insert metric] because [insert reason].
Make sure your goals are directly related to the experiment. If you are testing your CTA button, the goal should be getting more users to click the button. It shouldn’t be a goal further down the conversion funnel, like making a purchase.
Start with A/B tests
A/B testing is one of the easiest and most effective ways to run experiments to improve your current conversion rate. So, it’s no wonder that the A/B testing software market was expected to be worth $1.2 billion in 2023 and hit $3.6 billion by 2033.
Also known as split testing, A/B testing allows you to directly compare the conversion performance of two elements on your page, like the colour of your CTA button or your headline copy.
You can go even further with multivariate testing, which lets you test two or more changes against a single control.
For example, the screenshot above shows the results of a multivariate test between a standard header, a wide header and a small header using Matomo’s A/B testing tool. As you can see, the wider header has a much higher conversion, and the increase was statistically significant.
Try Matomo for Free
Get the web insights you need, without compromising data accuracy.
Tweak your CTAs
Calls to action (CTAs) are page elements that prompt users to respond immediately. They are usually buttons but can also be images or plain text links.
What your CTAs say, how they look, and where they are placed can greatly impact your site’s conversion rates. As such, this is one of the elements you’ll want to optimise first.
There are several tweaks you can test, including your CTA’s :
- Colour
- Length
- Copy
- Placement
You can even test the impact of removing CTA banners and using text-based CTAs on your conversion rates.
You should test out personalising CTAs, too. Research shows that personalised CTAs perform 202% better than standard calls to action.
Revise your web copy
You can use several strategies to improve your website’s copy and generate more conversions.
Optimising copy for search engines can increase traffic and generate more conversions, for example. But that shouldn’t make your copy any less impactful. Bear search engines in mind, by all means, but make sure you are speaking to the needs and desires of your potential customers. Your copy needs to convince users that your product can solve their problems.
Nowhere is this more important than your headlines. These will be the first thing users read, so make sure they sell your USP and highlight pain points.
Don’t just guess at the kind of messaging that will move the needle, however. Constantly test new headlines and continue doing so even after you’ve started seeing success. The results may surprise you. TruckersReport, a site that helps people become truck drivers, boosted opt-ins by 21.7% by revising its landing page headline, among other changes.
Make sure there are no spelling mistakes in your copy, either. Misspelt words, poor grammar and bad formatting make your website look unprofessional and untrustworthy. Even if the rest of your copy is incredibly enticing, these rookie errors can be enough to turn customers off.
Simplify your site’s navigation
A website’s navigation is an often overlooked factor in conversion rate optimisation, but simplifying it can make it much easier for users to take action.
If you’ve ever used a poorly designed e-commerce store, you know how confusing and overwhelming bad navigation can be. Research shows that a whopping 82% of stores don’t divide their navigation into manageable chunks.
The trick is to simplify your navigation as much as possible. As you can see in the screenshot below, our navigation only has five headers and a call to action. It’s easy to find exactly what you’re looking for, and you can’t miss the big green CTA button.
Alternatively, you can test what happens when you completely remove your navigation. Brands usually do this on landing pages where the only action they want the user to take is to make a purchase.
It’s exactly the strategy we’ve used on our free trial landing page.
Leverage heatmaps
Analytics tools — and heatmaps in particular — can help you understand user behaviour and optimise accordingly.
Heatmaps are a visual representation of user interaction on your page. Red and yellow represent high levels of user interaction, and blue and green represent low levels of interaction.
As you can see in the screenshot above, our CTA button has some of the highest levels of engagement on the page, telling us that it’s well-positioned. Given the focus on the site’s navigation, we can also assume we are correct to have a CTA button in there — something we can confirm using our web analytics to see how many users click on it.
Reduce load time
Speed matters when it comes to conversions. Fact.
Research shows a huge difference in conversion rates between quick and slow sites. For example, a site that loads in one second converts three times better than a site that loads in five seconds.
That’s why using a web analytics tool is vital to understand page load times and act accordingly if you think slow speeds are hampering your conversions.
Identifying your slowest pages is easy with Matomo. Just sort your pages by the Avg. Use the page load time metric on the page performance report to identify the pages you want to drive conversions.
Next, take steps to improve your page’s load time by :
- Compressing images
- Compressing code files or using a more lightweight theme
- Removing unnecessary plugins
- Using a content delivery network
- Improving your hosting
Try Matomo for Free
Get the web insights you need, without compromising data accuracy.
Add more trust signals
Trust is essential when you’re trying to convince customers to make a purchase. In fact, consumers rate trust as one of the top three buying factors, far above a brand’s reputation and whether they love the brand.
Adding trust signals to your landing pages, such as customer testimonials, customer reviews, case studies, and other forms of social proof, can transform your conversion rates. If consumers see real people and businesses buy from you, they’ll feel reassured to do the same.
It’s a strategy we use ourselves. Just look at the screenshot from our homepage above. Immediately after our free trial CTA, we display the logos of well-known brands that use our product.
Security-focused trust signals are also powerful if you are an online store. Installing an SSL certificate, showing logos of trusted payment providers (like PayPal and Mastercard) can convince people they are spending money at a legitimate store.
Improve your site’s mobile experience
More and more people are accessing the internet via their smartphones. In 2022, for instance, there were five billion unique mobile Internet users, meaning more than 60% of the internet population used a smartphone to browse online.
Moreover, 76% of U.S. adults make purchases using their smartphones.
That means you need to ensure your site’s mobile experience is on-point to increase conversions.
Your site should use a mobile-first design, meaning it works perfectly on smartphones and then scales up for desktop users.
Trust the data
Opinions are a fantastic form of inspiration for new A/B tests. But they should never be trusted over cold, hard data. If your test shows the opposite of what you and your team thought would happen, then trust the data and not yourself.
With that in mind, ensure you collect qualitative and quantitative data during your experiments. Web analytics should always form the backbone of conversion tests, but don’t forget to also use heatmaps, screen recordings, and customer surveys.
Keep testing
There’s no such word as “finished” in the world of A/B testing. Continual testing is key if you want to convert more website visitors.
Make sure you aren’t stopping tests prematurely, either. Make sure every A/B and multivariate test reaches a sample size that makes the test statistically significant.
Understand your users better with Matomo
Whether you run an e-commerce store, a SaaS company, or a service-based business, implementing these conversion rate optimisation best practices could be an easy way to lower your bounce rate and boost your conversion rates.
But remember, best practices aren’t clear-cut rules. What works for one website may not work for yours. That’s why running your own tests and understanding your visitors’ behaviour is important.
Matomo’s web analytics platform is the perfect tool for doing just that. Not only does it come with the tools you need to optimise your conversion rate (like an A/B testing tool, heatmaps and session recordings), but you can also trust the data. Unlike Google Analytics 4 and other tools, Matomo doesn’t use data sampling meaning you have 100% accurate data from which to make better decisions. It’s GDPR compliant and can run cookieless, so no need for cookie consent banners (excluding in the UK and Germany).
Discover how you can improve your website’s conversions with Matomo by starting a free 21-day trial, no credit card required.
Try Matomo for Free
21 day free trial. No credit card required.
-
RTMP server with OpenCV (python)
12 février, par OvernoutI'm trying to process an RTMP stream in Python, using OpenCV2 but I'm not able to get OpenCV to capture it (i.e. act as RTMP server).


I can run FFmpeg/FFplay from the command line and receive the stream successfully.
What could cause OpenCV to fail opening the stream in listening mode ?


Here is my code :


import cv2

cap = cv2.VideoCapture("rtmp://0.0.0.0:8000/live", cv2.CAP_FFMPEG)

if not cap.isOpened():
 print("Cannot open video source")
 exit()


And the output :


[tcp @ 00000192c490d640] Connection to tcp://0.0.0.0:8000 failed: Error number -138 occurred
[rtmp @ 00000192c490d580] Cannot open connection tcp://0.0.0.0:8000 
Cannot open video source


edit2 : Output with debug logging turned on :


output of the python script with debug logging on:
[DEBUG:0@0.017] global videoio_registry.cpp:218 cv::`anonymous-namespace'::VideoBackendRegistry::VideoBackendRegistry VIDEOIO: Builtin backends(9): FFMPEG(1000); GSTREAMER(990); INTEL_MFX(980); MSMF(970); DSHOW(960); CV_IMAGES(950); CV_MJPEG(940); UEYE(930); OBSENSOR(920)
[DEBUG:0@0.026] global videoio_registry.cpp:242 cv::`anonymous-namespace'::VideoBackendRegistry::VideoBackendRegistry VIDEOIO: Available backends(9): FFMPEG(1000); GSTREAMER(990); INTEL_MFX(980); MSMF(970); DSHOW(960); CV_IMAGES(950); CV_MJPEG(940); UEYE(930); OBSENSOR(920)
[ INFO:0@0.031] global videoio_registry.cpp:244 cv::`anonymous-namespace'::VideoBackendRegistry::VideoBackendRegistry VIDEOIO: Enabled backends(9, sorted by priority): FFMPEG(1000); GSTREAMER(990); INTEL_MFX(980); MSMF(970); DSHOW(960); CV_IMAGES(950); CV_MJPEG(940); UEYE(930); OBSENSOR(920)
[ WARN:0@0.037] global cap.cpp:132 cv::VideoCapture::open VIDEOIO(FFMPEG): trying capture filename='rtmp://192.168.254.101:8000/live' ...
[ INFO:0@0.040] global backend_plugin.cpp:383 cv::impl::getPluginCandidates Found 2 plugin(s) for FFMPEG
[ INFO:0@0.043] global plugin_loader.impl.hpp:67 cv::plugin::impl::DynamicLib::libraryLoad load C:\Users\me\src\opencv\.venv\Lib\site-packages\cv2\opencv_videoio_ffmpeg490_64.dll => OK
[ INFO:0@0.047] global backend_plugin.cpp:50 cv::impl::PluginBackend::initCaptureAPI Found entry: 'opencv_videoio_capture_plugin_init_v1'
[ INFO:0@0.049] global backend_plugin.cpp:169 cv::impl::PluginBackend::checkCompatibility Video I/O: initialized 'FFmpeg OpenCV Video I/O Capture plugin': built with OpenCV 4.9 (ABI/API = 1/1), current OpenCV version is '4.9.0' (ABI/API = 1/1)
[ INFO:0@0.055] global backend_plugin.cpp:69 cv::impl::PluginBackend::initCaptureAPI Video I/O: plugin is ready to use 'FFmpeg OpenCV Video I/O Capture plugin'
[ INFO:0@0.058] global backend_plugin.cpp:84 cv::impl::PluginBackend::initWriterAPI Found entry: 'opencv_videoio_writer_plugin_init_v1'
[ INFO:0@0.061] global backend_plugin.cpp:169 cv::impl::PluginBackend::checkCompatibility Video I/O: initialized 'FFmpeg OpenCV Video I/O Writer plugin': built with OpenCV 4.9 (ABI/API = 1/1), current OpenCV version is '4.9.0' (ABI/API = 1/1)
[ INFO:0@0.065] global backend_plugin.cpp:103 cv::impl::PluginBackend::initWriterAPI Video I/O: plugin is ready to use 'FFmpeg OpenCV Video I/O Writer plugin'
[tcp @ 00000266b2f0d0c0] Connection to tcp://192.168.254.101:8000 failed: Error number -138 occurred
[rtmp @ 00000266b2f0cfc0] Cannot open connection tcp://192.168.254.101:8000
[ WARN:0@5.630] global cap.cpp:155 cv::VideoCapture::open VIDEOIO(FFMPEG): can't create capture
[DEBUG:0@5.632] global cap.cpp:225 cv::VideoCapture::open VIDEOIO: choosen backend does not work or wrong. Please make sure that your computer support chosen backend and OpenCV built with right flags.
Cannot open video source
[ INFO:1@5.661] global plugin_loader.impl.hpp:74 cv::plugin::impl::DynamicLib::libraryRelease unload C:\Users\me\src\opencv\.venv\Lib\site-packages\cv2\opencv_videoio_ffmpeg490_64.dll


Here is the output of cv2.getBuildInformation()


General configuration for OpenCV 4.9.0 =====================================
 Version control: 4.9.0

 Platform:
 Timestamp: 2023-12-31T11:21:12Z
 Host: Windows 10.0.17763 AMD64
 CMake: 3.24.2
 CMake generator: Visual Studio 14 2015
 CMake build tool: MSBuild.exe
 MSVC: 1900
 Configuration: Debug Release

 CPU/HW features:
 Baseline: SSE SSE2 SSE3
 requested: SSE3
 Dispatched code generation: SSE4_1 SSE4_2 FP16 AVX AVX2
 requested: SSE4_1 SSE4_2 AVX FP16 AVX2 AVX512_SKX
 SSE4_1 (16 files): + SSSE3 SSE4_1
 SSE4_2 (1 files): + SSSE3 SSE4_1 POPCNT SSE4_2
 FP16 (0 files): + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 AVX
 AVX (8 files): + SSSE3 SSE4_1 POPCNT SSE4_2 AVX
 AVX2 (36 files): + SSSE3 SSE4_1 POPCNT SSE4_2 FP16 FMA3 AVX AVX2

 C/C++:
 Built as dynamic libs?: NO
 C++ standard: 11
 C++ Compiler: C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/bin/x86_amd64/cl.exe (ver 19.0.24247.2)
 C++ flags (Release): /DWIN32 /D_WINDOWS /W4 /GR /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /fp:precise /EHa /wd4127 /wd4251 /wd4324 /wd4275 /wd4512 /wd4589 /wd4819 /MP /O2 /Ob2 /DNDEBUG 
 C++ flags (Debug): /DWIN32 /D_WINDOWS /W4 /GR /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /fp:precise /EHa /wd4127 /wd4251 /wd4324 /wd4275 /wd4512 /wd4589 /wd4819 /MP /Zi /Ob0 /Od /RTC1 
 C Compiler: C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/bin/x86_amd64/cl.exe
 C flags (Release): /DWIN32 /D_WINDOWS /W3 /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /fp:precise /MP /O2 /Ob2 /DNDEBUG 
 C flags (Debug): /DWIN32 /D_WINDOWS /W3 /D _CRT_SECURE_NO_DEPRECATE /D _CRT_NONSTDC_NO_DEPRECATE /D _SCL_SECURE_NO_WARNINGS /Gy /bigobj /Oi /fp:precise /MP /Zi /Ob0 /Od /RTC1 
 Linker flags (Release): /machine:x64 /NODEFAULTLIB:atlthunk.lib /INCREMENTAL:NO /NODEFAULTLIB:libcmtd.lib /NODEFAULTLIB:libcpmtd.lib /NODEFAULTLIB:msvcrtd.lib
 Linker flags (Debug): /machine:x64 /NODEFAULTLIB:atlthunk.lib /debug /INCREMENTAL /NODEFAULTLIB:libcmt.lib /NODEFAULTLIB:libcpmt.lib /NODEFAULTLIB:msvcrt.lib
 ccache: NO
 Precompiled headers: YES
 Extra dependencies: wsock32 comctl32 gdi32 ole32 setupapi ws2_32
 3rdparty dependencies: libprotobuf ade ittnotify libjpeg-turbo libwebp libpng libtiff libopenjp2 IlmImf zlib ippiw ippicv

 OpenCV modules:
 To be built: calib3d core dnn features2d flann gapi highgui imgcodecs imgproc ml objdetect photo python3 stitching video videoio
 Disabled: java world
 Disabled by dependency: -
 Unavailable: python2 ts
 Applications: -
 Documentation: NO
 Non-free algorithms: NO

 Windows RT support: NO

 GUI: WIN32UI
 Win32 UI: YES
 VTK support: NO

 Media I/O: 
 ZLib: build (ver 1.3)
 JPEG: build-libjpeg-turbo (ver 2.1.3-62)
 SIMD Support Request: YES
 SIMD Support: NO
 WEBP: build (ver encoder: 0x020f)
 PNG: build (ver 1.6.37)
 TIFF: build (ver 42 - 4.2.0)
 JPEG 2000: build (ver 2.5.0)
 OpenEXR: build (ver 2.3.0)
 HDR: YES
 SUNRASTER: YES
 PXM: YES
 PFM: YES

 Video I/O:
 DC1394: NO
 FFMPEG: YES (prebuilt binaries)
 avcodec: YES (58.134.100)
 avformat: YES (58.76.100)
 avutil: YES (56.70.100)
 swscale: YES (5.9.100)
 avresample: YES (4.0.0)
 GStreamer: NO
 DirectShow: YES
 Media Foundation: YES
 DXVA: YES

 Parallel framework: Concurrency

 Trace: YES (with Intel ITT)

 Other third-party libraries:
 Intel IPP: 2021.11.0 [2021.11.0]
 at: D:/a/opencv-python/opencv-python/_skbuild/win-amd64-3.7/cmake-build/3rdparty/ippicv/ippicv_win/icv
 Intel IPP IW: sources (2021.11.0)
 at: D:/a/opencv-python/opencv-python/_skbuild/win-amd64-3.7/cmake-build/3rdparty/ippicv/ippicv_win/iw
 Lapack: NO
 Eigen: NO
 Custom HAL: NO
 Protobuf: build (3.19.1)
 Flatbuffers: builtin/3rdparty (23.5.9)

 OpenCL: YES (NVD3D11)
 Include path: D:/a/opencv-python/opencv-python/opencv/3rdparty/include/opencl/1.2
 Link libraries: Dynamic load

 Python 3:
 Interpreter: C:/hostedtoolcache/windows/Python/3.7.9/x64/python.exe (ver 3.7.9)
 Libraries: C:/hostedtoolcache/windows/Python/3.7.9/x64/libs/python37.lib (ver 3.7.9)
 numpy: C:/hostedtoolcache/windows/Python/3.7.9/x64/lib/site-packages/numpy/core/include (ver 1.17.0)
 install path: python/cv2/python-3

 Python (for build): C:\hostedtoolcache\windows\Python\3.7.9\x64\python.exe

 Java: 
 ant: NO
 Java: YES (ver 1.8.0.392)
 JNI: C:/hostedtoolcache/windows/Java_Temurin-Hotspot_jdk/8.0.392-8/x64/include C:/hostedtoolcache/windows/Java_Temurin-Hotspot_jdk/8.0.392-8/x64/include/win32 C:/hostedtoolcache/windows/Java_Temurin-Hotspot_jdk/8.0.392-8/x64/include
 Java wrappers: NO
 Java tests: NO

 Install to: D:/a/opencv-python/opencv-python/_skbuild/win-amd64-3.7/cmake-install
-----------------------------------------------------------------


edit : Receiving the stream with ffplay from command line :


>ffplay.exe -i "rtmp://0.0.0.0:8000/live" -listen 1 -f flv
ffplay version 2024-02-04-git-7375a6ca7b-full_build-www.gyan.dev Copyright (c) 2003-2024 the FFmpeg developers
 built with gcc 12.2.0 (Rev10, Built by MSYS2 project)
 configuration: --enable-gpl --enable-version3 --enable-static --pkg-config=pkgconf --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libaribb24 --enable-libaribcaption --enable-libdav1d --enable-libdavs2 --enable-libuavs3d --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libaom --enable-libjxl --enable-libopenjpeg --enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libharfbuzz --enable-liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-dxva2 --enable-d3d11va --enable-libvpl --enable-libshaderc --enable-vulkan --enable-libplacebo --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libcodec2 --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
 libavutil 58. 36.101 / 58. 36.101
 libavcodec 60. 38.100 / 60. 38.100
 libavformat 60. 20.100 / 60. 20.100
 libavdevice 60. 4.100 / 60. 4.100
 libavfilter 9. 17.100 / 9. 17.100
 libswscale 7. 6.100 / 7. 6.100
 libswresample 4. 13.100 / 4. 13.100
 libpostproc 57. 4.100 / 57. 4.100
[rtmp @ 0000018a564ed340] Unexpected stream , expecting livef=0/0
 Last message repeated 1 times
Input #0, flv, from 'rtmp://0.0.0.0:8000/live':KB sq= 0B f=0/0
 Metadata:
 fileSize : 0
 audiochannels : 2
 2.1 : false
 3.1 : false
 4.0 : false
 4.1 : false
 5.1 : false
 7.1 : false
 encoder : obs-output module (libobs version 30.0.2)
 Duration: 00:00:00.00, start: 0.000000, bitrate: N/A
 Stream #0:0: Audio: aac (LC), 48000 Hz, stereo, fltp, 163 kb/s
 Stream #0:1: Video: h264 (Constrained Baseline), yuv420p(tv, bt709, progressive), 1280x720 [SAR 1:1 DAR 16:9], 2560 kb/s, 30 fps, 30 tbr, 1k tbn
 7.54 A-V: -0.024 fd= 18 aq= 24KB vq= 498KB sq= 0B f=0/0


-
Split video with ffmpeg segment option is missing frame
9 février, par DanI’m trying to get the ffmpeg “segment” option to split my video into segments at the Iframes. I'm using ffmpeg V6.1.1.


First I added time stamps to each frame of my video so that when it plays, I can see exactly which frame is being displayed. I used this command :


ffmpeg -i In.mp4 -vf "drawtext=fontfile='C :\Windows\Fonts\Arial.ttf' : text='%frame_num :~ %pts':fontsize=200 : r=25 : x=(w-tw)/2 : y=h-(2*lh) : fontcolor=white : box=1 : boxcolor=0x00000099" -y Out.mp4


Then I used ffprobe to confirm that the video is 30 FPS and the Iframes are as follows :


0.000000
4.933333
10.000000
11.533333
18.866667
24.966667


Based on these Iframe times, I’d expect the following segments :







 Start Frame 

Start Time 

End Frame 

End Time 







 0 

0 

147 

4.900000 




 148 

4.933333 

299 

9.966667 




 300 

10.000000 

345 

11.500000 




 346 

11.533333 

565 

18.833334 




 566 

18.866667 

748 

24.933334 




 749 

24.966667 

867 

28.906667 









When I use ffmpeg to split the video into segments with the following command, I get six files as expected :


ffmpeg -i Out.mp4 -f segment -c copy -reset_timestamps 1 -map 0 "Out %d.mp4"


When I play the segments, they are all correct except the first segment file (Out 0.mp4). It seems to be missing the last frame. It contains frames 0 to 146 (4.866667 sec) but should also include frame 147 (4.9 sec). All the other segment files are as expected.


I’ve tried this on several different mp4 videos and they all are missing the last frame on the first segments.


Any idea why my first segment files is missing the last frame of the segment ?


Could this be an ffmpeg bug ?


Thanks for the help !
Dan


Here is my console session with all output :


C:\> ffprobe Out.mp4
ffprobe version 2023-12-21-git-1e42a48e37-full_build-www.gyan.dev Copyright (c) 2007-2023 the FFmpeg developers
 built with gcc 12.2.0 (Rev10, Built by MSYS2 project)
 configuration: --enable-gpl --enable-version3 --enable-static --pkg-config=pkgconf --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libaribb24 --enable-libaribcaption --enable-libdav1d --enable-libdavs2 --enable-libuavs3d --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libaom --enable-libjxl --enable-libopenjpeg --enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libharfbuzz --enable-liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-dxva2 --enable-d3d11va --enable-libvpl --enable-libshaderc --enable-vulkan --enable-libplacebo --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libcodec2 --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
 libavutil 58. 36.100 / 58. 36.100
 libavcodec 60. 36.100 / 60. 36.100
 libavformat 60. 20.100 / 60. 20.100
 libavdevice 60. 4.100 / 60. 4.100
 libavfilter 9. 14.100 / 9. 14.100
 libswscale 7. 6.100 / 7. 6.100
 libswresample 4. 13.100 / 4. 13.100
 libpostproc 57. 4.100 / 57. 4.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Out.mp4':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2avc1mp41
 title : Short 4k video sample - 4K Ultra HD (3840x2160)
 date : 2014:05:24 19:00:00
 encoder : Lavf60.20.100
 Duration: 00:00:28.96, start: 0.000000, bitrate: 3181 kb/s
 Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(progressive), 1920x1080 [SAR 1:1 DAR 16:9], 3045 kb/s, 30 fps, 30 tbr, 15360 tbn (default)
 Metadata:
 handler_name : VideoHandler
 vendor_id : [0][0][0][0]
 encoder : Lavc60.36.100 libx264
 Stream #0:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s (default)
 Metadata:
 handler_name : SoundHandler
 vendor_id : [0][0][0][0]

C:\ ffprobe -loglevel error -skip_frame nokey -select_streams v:0 -show_entries frame=pts_time -of csv=print_section=0 Out.mp4
0.000000,
4.933333
10.000000
11.533333
18.866667
24.966667

C:\ ffmpeg -i Out.mp4 -f segment -c copy -reset_timestamps 1 -map 0 "Out %1d.mp4"
ffmpeg version 2023-12-21-git-1e42a48e37-full_build-www.gyan.dev Copyright (c) 2000-2023 the FFmpeg developers
 built with gcc 12.2.0 (Rev10, Built by MSYS2 project)
 configuration: --enable-gpl --enable-version3 --enable-static --pkg-config=pkgconf --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-bzlib --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libaribb24 --enable-libaribcaption --enable-libdav1d --enable-libdavs2 --enable-libuavs3d --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libaom --enable-libjxl --enable-libopenjpeg --enable-libvpx --enable-mediafoundation --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libharfbuzz --enable-liblensfun --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-dxva2 --enable-d3d11va --enable-libvpl --enable-libshaderc --enable-vulkan --enable-libplacebo --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libcodec2 --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
 libavutil 58. 36.100 / 58. 36.100
 libavcodec 60. 36.100 / 60. 36.100
 libavformat 60. 20.100 / 60. 20.100
 libavdevice 60. 4.100 / 60. 4.100
 libavfilter 9. 14.100 / 9. 14.100
 libswscale 7. 6.100 / 7. 6.100
 libswresample 4. 13.100 / 4. 13.100
 libpostproc 57. 4.100 / 57. 4.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Out.mp4':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2avc1mp41
 title : Short 4k video sample - 4K Ultra HD (3840x2160)
 date : 2014:05:24 19:00:00
 encoder : Lavf60.20.100
 Duration: 00:00:28.96, start: 0.000000, bitrate: 3181 kb/s
 Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(progressive), 1920x1080 [SAR 1:1 DAR 16:9], 3045 kb/s, 30 fps, 30 tbr, 15360 tbn (default)
 Metadata:
 handler_name : VideoHandler
 vendor_id : [0][0][0][0]
 encoder : Lavc60.36.100 libx264
 Stream #0:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s (default)
 Metadata:
 handler_name : SoundHandler
 vendor_id : [0][0][0][0]
Stream mapping:
 Stream #0:0 -> #0:0 (copy)
 Stream #0:1 -> #0:1 (copy)
[segment @ 00000195bbc52940] Opening 'Out 0.mp4' for writing
Output #0, segment, to 'Out %1d.mp4':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2avc1mp41
 title : Short 4k video sample - 4K Ultra HD (3840x2160)
 date : 2014:05:24 19:00:00
 encoder : Lavf60.20.100
 Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(progressive), 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 3045 kb/s, 30 fps, 30 tbr, 15360 tbn (default)
 Metadata:
 handler_name : VideoHandler
 vendor_id : [0][0][0][0]
 encoder : Lavc60.36.100 libx264
 Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s (default)
 Metadata:
 handler_name : SoundHandler
 vendor_id : [0][0][0][0]
Press [q] to stop, [?] for help
[segment @ 00000195bbc52940] Opening 'Out 1.mp4' for writing
[segment @ 00000195bbc52940] Opening 'Out 2.mp4' for writing
[segment @ 00000195bbc52940] Opening 'Out 3.mp4' for writing
[segment @ 00000195bbc52940] Opening 'Out 4.mp4' for writing
[segment @ 00000195bbc52940] Opening 'Out 5.mp4' for writing
[out#0/segment @ 00000195bc3e8cc0] video:10757kB audio:456kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
size=N/A time=00:00:28.86 bitrate=N/A speed= 322x


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