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• Best intra-frame codec for editing ? Having color issues with DNxHR and serious sync issues with Prores

  23 janvier 2020, par Raulo1985

  I have a couple of questions regarding intra-frame codecs for editing purposes (in Premiere Pro).

  A LITTLE CONTEXT :

  I ripped a HDR movie to a MP4 container some months ago, using H.264 as codec (high 10, level 5, UHD, YUV, subsampling 4:2:0). The video looks great, as it should. Now I want to edit a trailer for that movie (I edit in Adobe Premiere Pro, current version), and for fast playback I need to work with proxies or transcode the source file to an intra-frame non long GOP file and use it as the source file (hopefully as lossless as that transcoding step can be). I tried for several days to transcode the source file to DNxHR 444 10 bits (using FFmpeg and then Adobe Media Encoder), but the result was always a video with the colors messed up (sometimes very washed out, sometimes over saturated).

  FFprobe of the resulting DNxHR file said that the color space was BT709 (source file is obviously BT2020), and I don’t know why. The transcoding involved upsampling since the source file is 4:2:0 and DNxHR doesn’t support it, but I tried upsampling to 4:4:4 and also to 4:2:2, and both of those files looked exactly the same to me, and very different from the original footage (so, I don’t think upsampling is the cause of the color issue, but maybe the apparent color space change or something wrong with the metadata). The results were the same when transcoding with Adobe Media Encoder. Anyway, I seem to have given up transcoding to DNxHR and use it as the source file, unless someone has an idea of what’s causing this problem. I could have worked with the source file for exporting and DNxHR LB for proxies, but there were sync issues (between source file and proxy) that defeated all purposes while editing. Prores is out of the picture, sync issues were worse (several seconds of delay).

  For the record, the command used that didn’t work as expected (color wise) is :

  ffmpeg -channel_layout 63 -i input.mkv -map 0:0 -c:v dnxhd -vf "scale=in_range=limited:out_range=full" -color_range 2 -profile:v dnxhr_444 -pix_fmt yuv444p10le -acodec pcm_s24le -ar 48000 -ac 6 -channel_layout 63 -map 0:2 -hide_banner output.mxf

  I also tried without the commands "scale=in_range=limited:out_range=full" and "-color_range 2", with same results. Always used FFmpeg latest version, and I’m working in Windows 10 Pro, latest drivers and latest Klite codec pack. Video files were compared with Mediainfo, FFprobe, and visually with VLC.

  Well, like I said, I’m giving up using DNxHR as the source file for my project (it would have been ideal since it doesn’t have sync issues with the DNxHR proxies, and file size is not a problem for me). A user here at the forums suggested transcoding and use H.264 intra-frame as source file, which I didn’t know was an option (I didn’t know H.264 was capable of intra-frame, my bad). I’m aware that one should avoid unnecesary transcoding steps, but I can’t work with a H.264 UHD HDR source file (ultra slow playback), and the sync issues with proxies, no matter the codec, make it impossible to make accurate cuts.
  So, bottom line, I need to find a way to fix the color issue when transcoding to DNxHR, or try with an inter-frame codec that’s not DNxHR and that’s capable of preserving all the HDR info (and then see if it doesn’t have sync issues. I’m assuming that those may dissapear when using intra-frame for both source file and proxies).

  NOTE : When importing the DNxHR 444 file to Premiere Pro and looking at the Lumetri scopes tab, you can tell that the colors are clipped at 100 nits, like a regular SDR video. So apparently the color space was really reduced to BT709, and I don’t know why. The H.264 source file behaves as expected, with colors going past 100 nits.

  MY QUESTIONS :

  1) Is H.264 intra-frame a good format for editing with a good playback performance ?

  2) If H.264 intra-frame is a good option, what would be the advantages of the DNxHR codec (or Prores) over it for editing purposes ? Everybody suggests DNxHD/DNxHR or Prores as intermediate codecs, but if intra-frame H.264 has the same advantages for editing and supports HDR, what would be the reason to choose another codec like DNxHR ?

  3) Any ideas on what could be the cause of the colors not transcoding correctly from the H.264 source file to the DNxHR 444 10 bits one ? The command looks ok to me, but FFprobe output says the DNxHR video is BT709, while with the source file it says BT2020. Like I said, apparently there’s something wrong with the transcoding process regarding metadata or color space.

  4) I haven’t tried to transcode the source file to a DNxHR 444 10 bits video file, but in a MOV container. I don’t know how this works internally, but maybe the color issue has something to do with the container metadata or something. I may try this if there’s not another suggestion (transcoding this kind of files, as you know, takes time, so I’ll wait for some ideas first).

  NOTE : I tried to transcode the source file in the same way (DNxHR 444, 10 bits, etc) with Adobe Media Encoder 2020 and the result was the same, with colors messed up and FFprobe saying the video is BT709. Also tried transcoding to DNxHR HQX profile (10 bits), same result.

  Any help would be greatly appreciated.

  Thanks in advance.

• avformat/mxfenc : Write Mastering Display Colour Volume to MXF

  9 septembre 2020, par Harry Mallon

  avformat/mxfenc : Write Mastering Display Colour Volume to MXF
  Described in Annex B SMPTE ST 2067-21:2020
  Signed-off-by : Harry Mallon <harry.mallon@codex.online>
  

  • [DH] libavformat/mxfenc.c

• How to increase conversions to meet your business goals

  8 septembre 2020, par Joselyn Khor — Analytics Tips, Marketing
   Through optimizing your messaging, content, or your page layouts, you can increase conversions by getting your visitors through a clear pathway to achieve your business goals.

  Conversion Rate Optimization

  When we talk about optimizing websites to improve and increase conversions, we’re really talking about conversion rate optimization (CRO).

  CRO is the process of learning what the most valuable content/aspect of your website is and how to best optimize this for your visitors to increase its chance to convert. It typically involves generating ideas for elements on your site or app that can be improved, learning which pathways visitors are most likely going to take to conversion and then validating those assumptions through A/B testing and multivariate testing to transform learning into actionable insights.

  Conversion Rate

  The conversion rate is expressed as a % and the goal for any business should be to increase the % of conversions for any given goal e.g. in February a website had 200 newsletter sign-ups from 1,000 visitors on its sign-up page, a conversion rate of 20%. CRO should be used to increase the sign-up rate from 20% to 25%, and then eventually from 25% to 30% and so on.

  CRO cheat sheet

  You need to consider your website or business’ objectives (bigger picture) as well as your website goals (smaller achievements). Whatever the aim of your website, it’s crucial for this to be your starting point. Figure out what you want your website to do and what you want visitors to get from it. When you do that, you’ll know what conversions to focus on.
  

  • Define your business/website’s objectives. Do you want the website to drive sales ? Is the website a hub to raise awareness for a charity ? Do you want to increase readership for your news site ?
  • Define what your conversion goals are. This helps you narrow your focus so you follow a path to meet your overall objectives. By defining these, you clarify for yourself the next actions you should take, such as wanting to funnel users through to a sign up landing page. Then you’ll need to optimize and test your sign up landing page. If conversions are low, then tweak it and measure the results until you find you’ve increased conversion rates.
  • Conversion goals can include :
    • Purchases in your ecommerce store
    • eBook downloads
    • Sign ups to your mailing list
    • Visitors successfully filling in a contact form
  • Figure out what your Key Performance Indicators (KPIs) are and the metrics you need to focus on to achieve them.

  How to increase conversions with Matomo

  1. Set goals
  2. Heatmaps
  3. Session Recordings
  4. A/B test
  5. Form Analytics
  6. Funnels
  7. Behaviour

  1. Set goals

  “Make Sure Goals Are Clearly Understood. To prove the value of an analytics-focused company, any project you take on needs to have clear goals. If you don’t have a goal in mind you’ll fail. Everyone involved in the project needs to be aligned around the goals.”

  A goal is the measure of a successful action that you want your visitors to take. The more goals you track, the more you can learn about behavioural changes as you implement and modify paths that lead to conversions over time.

  

  You’ll understand which channels and campaigns (SEO, PPC, newsletter, blogging etc.) are converting the best for your business, which cities/countries are most popular, what devices are working and how engaged your visitors are before converting. Learn more

  2. Set Heatmaps

  This is vital to show how your visitors are engaging with your website, blog pages, signup and sales pages. If you want to learn how your visitors really engage with your website to increase conversions, Heatmaps lets you see the results visually without any guesswork.

  

  By showing where your visitors try to click, move the mouse or how far down they’re scrolling on each page, you can effortlessly discover how your visitors truly engage with your most important web pages. Rather than guessing, rely on facts to prove if the changes you make actually improve your website or not. Learn more

  How to improve conversion rates with Heatmaps :

  • If you’ve got important information that will sell your service/product or bring you loyal followers, make sure it’s in the hot zones as shown in your heatmaps.
  • Try to rearrange parts of your pages to see if that increases engagement.
  • Make it easy for people to take important actions by having the CTA above-the-fold where 100% of visitors see it. Make sure you don’t clutter this section with too many messages or actions.
  • You can also identify areas to add links as heatmaps shows where people want to click.
  • Find what content is most popular on the page

  3. Session Recordings

  This is a conversion research technique where you learn what your users are trying to do and make sure your website is optimized to give them what they want. With Session Recordings you can playback all the interactions your visitors took on your website, such as clicks, mouse movements, scrolls, resizes, form interactions and page changes in a video. Truly understand how real visitors are using your website and what experiences they’re having.

  Also, by understanding what’s working you’re increasing the usability of your website, Session Recordings allow you to identify problem areas as well as where users are getting stuck. Learn more

  

  How to improve conversion rates with Session Recordings : For example, on a product landing page, you see your visitor highlighting specific words and putting it into search. With this you can observe what they’re trying to find and what they’re actually interested in. As you tweak the page to ensure what the visitor wants can be easily found, you’re taking steps to increase the chance for more conversions.

  4. A/B Testing

  Test anything and test anywhere to increase your conversions. Grow your website by comparing different versions of your landing pages to determine what works best for your users. Subtle tweaks across different versions of your landing pages can have a significant impact on converting incoming traffic.

  

  The changes for each landing page could be :

  • A different headline
  • Less copy vs more copy
  • Different calls-to-action
  • Colour schemes, forms, fonts, links, testimonials,
  • Or, it could be an entirely different page layout altogether.

  The idea is to see if either page A or page B (or C or D) was most successful in getting your visitors to the next step in the conversion funnel. Learn more

  How Matomo used A/B Testing : For our sign up page we tested three different CTAs and found how phrasing words differently could help improve conversion rates. Both “Start improving your websites” and “Start converting more users now” were stronger CTAs and converted 7% more than, “Start my free 30-day trial”.

  5. Form Analytics

  Form Analytics gives you powerful insights into how your visitors interact with your forms (like cart, sign-up and checkout forms).

  

  Online forms can come in thousands of different variations. It’s an area on your website that if not done right, could lead to you missing out on converting a large portion of your visitors. Rely on facts when you change your forms. Learn more

  How to improve conversion rates with Form Analytics : By proving whether your form is doing better when you change it and by how much. This lets you consistently increase form submission rates (conversions) on your website which is crucial to the success of your business.

  6. Funnels

  At a glance you will learn the steps (actions, events and pages) your users go through to the desired outcomes you want them to achieve whether it’s a sale, sign-up or any other particular goal you have defined.

  

  Looking at the entire conversion funnel and focusing on usability, you’ll be able to identify where your visitors are having problems, where they aren’t understanding the flow of your webpages and identify obstacles that get in the way of your users reaching that end goal. Learn more

  How to improve conversion rates with Funnels : Learn what makes your visitors take action (or what stops them) in progressing to the next step in the conversion funnel. At each step, you’ll discover what content/layout resonates with your visitors and you can optimize your website to have the greatest impact on your business.

  TRY IT FOR FREE

  7. Behaviour

  This is one of the most important features to help you optimize your website for conversions. Learning visitor behaviour is a driving force to increase conversions. How ? It lets you identify where you could be taking action to increase conversions. You get to learn first-hand what content or feature on your site is or isn’t working for your visitors. 

  

  Engagement is essential to help increase conversion rates. If your visitors aren’t interested in the content on your site, then there’s very little chance they’ll be interested in what you have to offer. Learn more

  How to improve conversion rates with Behaviour : Get started by reducing bounce rates on important pages, testing messaging on your most popular entry pages, testing on the highest exit pages to reduce visitors leaving the site, learning pathways through Users Flow and Transitions to see if users are taking pathways that lead them to conversions or are the journeys currently long or go in odd directions. Discover how your visitors are responding to your content. The happier your visitors are to stay on your site, the more likely they’ll be able to move through the journey to help you achieve the goals you’ve set for your site.

  TRY IT FOR FREE

  Do privacy-focused industries need conversion optimization ?

  For industries that place extra emphasis on privacy and security, Matomo is a complete analytics tool that can cater for all your needs. You get the full benefits of a web analytics and conversion optimization platform as well as peace of mind knowing Matomo places emphasis on security/privacy and adheres strictly to GDPR.

  If you operate in a data sensitive industry like in government, healthcare, finance, education etc. you can rest assured knowing your user’s privacy is respected and that you will have 100% data ownership.

  Other conversion optimization metrics in Matomo to look at :

  Get a good indication that your conversion optimization efforts are working by knowing where to look and this starts by going through the metrics in your analytics. Below we list how you can make a start.

  “Best” metrics are hard to determine so you’ll need to ask yourself what you want your site to do. How do you want your users to behave or what kind of customer journey do you want them to have ?

  You can start with :

  • Decreasing abandonment rate
  • Decreasing bounce rate
  • Increasing interactions per visit
  • Reducing exit rates on pages that significantly impact your visitors to leave your site
  • Constantly test and learn what content resonates with your visitors
  • Look to advance more users through each stage of the conversion funnel
  • Improve your forms to increase submission rates
  • Always improve the conversion rate % for your goals e.g. if you currently have a 5% conversion rate for selling a product, aim for 10% ; if 30% of your visitors are downloading your e-book, then aim for 40%, then 50% and so on.

  Through optimizing your messaging, content or your page layouts, you will increase conversions by getting your visitors through a clear pathway to meet your website’s goal.

  TRY IT FOR FREE