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• Q&A : An interview with Matomo founder, Matthieu Aubry

  20 novembre 2018, par Joselyn Khor — About, Community

  Hey everyone ! Joselyn here. As always the views of our community remain top of mind. So to make sure you guys know the thinking behind these new projects, we reached out to Matomo’s founder, Matthieu, to ask questions you might want answered. Please check it out below !

  Hi guys, it’s Matthieu ! Here to answer some questions about the rebrand and the future of Matomo and Innocraft.

  What’s upcoming ?

  We’ve been busy implementing our rebrand into all aspects of Matomo and there’s also our new website, which is launching today ! The new website will help people better understand what Matomo is and how they can benefit from using modern web analytics.

  Why was Matomo and Innocraft brought onto one website ?

  In the past the separation caused a bit of confusion so we’re taking this as a chance to unite both the business brand, Innocraft and community brand, Matomo, on one website. Putting our focus on one brand, Matomo, makes it easier for people to see us with fresh eyes. We have a community side as well as a business side and while the community is still incredibly important to us, we find we have a powerful analytics tool that is capable of helping businesses too.

  Is Matomo becoming commercial or turning corporate ?

  No. nothing is changing. Matomo is still an open-source project and community. Although we’ll have a pricing page and “start free trial” on the new website brought over from Innocraft.cloud, the Matomo community will still play the biggest part on the Matomo website. We have dedicated sections focused on Community and On-Premise.

  The rebrand exercise helped us gain a refreshed perspective. After reflecting on how far we’ve come, we can feel more confident about Matomo Analytics itself as a platform. We believe it’s a great chance to bring that confidence into the brand and vision. We are proud that it’s an awesome open-source platform and at the same time it’s also powerful as a tool for businesses.

  Why is there no ‘download for free’ button on the homepage ?

   

  
  We feel many users coming to the site will get confused about our hosting options (Cloud and On-Premise) which is something you don’t usually consider when choosing an analytics tool.

  The reason for us to not have that button is when people see a “download for free” button on the homepage next to a “try it for free” button, it creates confusion. For those who do choose to download Matomo often become confused when they are left with a .zip file unaware how to install it and the technical requirements of self-hosting. We feel presenting our users with the simplest installation option first will give them the best chance possible to try Matomo to its full potential, without cost.

  And you can still find the link to Download Matomo in the footer of each page.
  

   

  Is Matomo still free to download and have forever ?

  Absolutely. The free open-source download can be found on the On-Premise section of the website, or download Matomo here.

  Why is it important to have a business behind the project ?

  There’s the reality that we have to make money in order for the Matomo project to survive … and thrive. The reason we still need a business side (Innocraft) is to fund and sustain the Matomo project. Whenever people purchase premium features, this helps finance the development of Matomo for our community.

  Because of the business we’re able to continually maintain and develop Matomo for you guys as well as future users. For example, the next release Matomo 3.8.0 is already mostly developed and will bring lots of interesting features too, like the two-factor authentication, Brute Force Protection, failed tracking requests reporting, lots of JavaScript tracker improvements, a new total summary row below reports, and many more security fixes, bug fixes, and other new features.

  So we see a business being very helpful in supporting our open-source community. Without a business side, our free, open-source project would not be able to survive.

  How will you protect the Matomo project ?

  We’ve ensured the Matomo project will be protected for the future as we wish to turn it into a not-for-profit foundation.

  We’ve also got a safeguard where the open-source code will stay under a GPL license forever. This is so we can guarantee, that no matter what happens, the Matomo project itself will stay completely free software.

  Is there a way for people to help ?

  There are heaps of ways to help ! You can help other Matomo users in the forums, contribute to fixes on GitHub, leave a great review (e.g. alternativeTo), help look for bugs with our Security Bounty Programme or participate and spread the word about Matomo in our community social media pages – Mastodon, Facebook, Twitter. Telling your friends about us would be very helpful too !

  What’s planned for the future ?
  We’ve worked hard to become the #1 open-source analytics platform (1.4 million websites use Matomo today), but now we need to empower even more individuals and businesses to take back control of their own data.

  Showing our community that we have a powerful platform is crucial, but alongside that our values are what define us. User privacy is still of utmost importance and we’re here to make it known that power needs to rest in the hands of people and not large corporations.

  You can rest easy knowing you’re doing your part in using trustworthy and dependable tools. By joining many other companies who are growing this movement to decentralise the Internet, we can build a safer, online world together.

  Join this analytics revolution and let us know what you think about Matomo !

• Inside WebM Technology : VP8 Intra and Inter Prediction

  20 juillet 2010, par noreply@blogger.com (Lou Quillio)
  Continuing our series on WebM technology, I will discuss the use of prediction methods in the VP8 video codec, with special attention to the TM_PRED and SPLITMV modes, which are unique to VP8.

  
  

  First, some background. To encode a video frame, block-based codecs such as VP8 first divide the frame into smaller segments called macroblocks. Within each macroblock, the encoder can predict redundant motion and color information based on previously processed blocks. The redundant data can be subtracted from the block, resulting in more efficient compression.

  
  Image by Fido Factor, licensed under Creative Commons Attribution License.
  Based on a work at www.flickr.com

  
  

  A VP8 encoder uses two classes of prediction :

  • Intra prediction uses data within a single video frame
  • Inter prediction uses data from previously encoded frames

  The residual signal data is then encoded using other techniques, such as transform coding.

  
  

  VP8 Intra Prediction Modes

  VP8 intra prediction modes are used with three types of macroblocks :

  • 4x4 luma
  • 16x16 luma
  • 8x8 chroma

  Four common intra prediction modes are shared by these macroblocks :
  

  • H_PRED (horizontal prediction). Fills each column of the block with a copy of the left column, L.
  • V_PRED (vertical prediction). Fills each row of the block with a copy of the above row, A.
  • DC_PRED (DC prediction). Fills the block with a single value using the average of the pixels in the row above A and the column to the left of L.
  • TM_PRED (TrueMotion prediction). A mode that gets its name from a compression technique developed by On2 Technologies. In addition to the row A and column L, TM_PRED uses the pixel P above and to the left of the block. Horizontal differences between pixels in A (starting from P) are propagated using the pixels from L to start each row.

  For 4x4 luma blocks, there are six additional intra modes similar to V_PRED and H_PRED, but correspond to predicting pixels in different directions. These modes are outside the scope of this post, but if you want to learn more see the VP8 Bitstream Guide.

  
  

  As mentioned above, the TM_PRED mode is unique to VP8. The following figure uses an example 4x4 block of pixels to illustrate how the TM_PRED mode works :

  

  Where C, As and Ls represent reconstructed pixel values from previously coded blocks, and X₀₀ through X₃₃ represent predicted values for the current block. TM_PRED uses the following equation to calculate X_ij :

  
  

  X_ij = L_i + A_j - C (i, j=0, 1, 2, 3)

  
  

  Although the above example uses a 4x4 block, the TM_PRED mode for 8x8 and 16x16 blocks works in the same fashion.

  TM_PRED is one of the more frequently used intra prediction modes in VP8, and for common video sequences it is typically used by 20% to 45% of all blocks that are intra coded. Overall, together with other intra prediction modes, TM_PRED helps VP8 to achieve very good compression efficiency, especially for key frames, which can only use intra modes (key frames by their very nature cannot refer to previously encoded frames).

  
  

  VP8 Inter Prediction Modes

  
  

  In VP8, inter prediction modes are used only on inter frames (non-key frames). For any VP8 inter frame, there are typically three previously coded reference frames that can be used for prediction. A typical inter prediction block is constructed using a motion vector to copy a block from one of the three frames. The motion vector points to the location of a pixel block to be copied. In most video compression schemes, a good portion of the bits are spent on encoding motion vectors ; the portion can be especially large for video encoded at lower datarates.

  
  

  Like previous VPx codecs, VP8 encodes motion vectors very efficiently by reusing vectors from neighboring macroblocks (a macroblock includes one 16x16 luma block and two 8x8 chroma blocks). VP8 uses a similar strategy in the overall design of inter prediction modes. For example, the prediction modes "NEAREST" and "NEAR" make use of last and second-to-last, non-zero motion vectors from neighboring macroblocks. These inter prediction modes can be used in combination with any of the three different reference frames.

  
  

  In addition, VP8 has a very sophisticated, flexible inter prediction mode called SPLITMV. This mode was designed to enable flexible partitioning of a macroblock into sub-blocks to achieve better inter prediction. SPLITMV is very useful when objects within a macroblock have different motion characteristics. Within a macroblock coded using SPLITMV mode, each sub-block can have its own motion vector. Similar to the strategy of reusing motion vectors at the macroblock level, a sub-block can also use motion vectors from neighboring sub-blocks above or left to the current block. This strategy is very flexible and can effectively encode any shape of sub-macroblock partitioning, and does so efficiently. Here is an example of a macroblock with 16x16 luma pixels that is partitioned to 16 4x4 blocks :

  
  

  

  
  

  where New represents a 4x4 bock coded with a new motion vector, and Left and Above represent a 4x4 block coded using the motion vector from the left and above, respectively. This example effectively partitions the 16x16 macroblock into 3 different segments with 3 different motion vectors (represented below by 1, 2 and 3) :

  
  

  

  
  

  Through effective use of intra and inter prediction modes, WebM encoder implementations can achieve great compression quality on a wide range of source material. If you want to delve further into VP8 prediction modes, read the VP8 Bitstream Guide or examine the reconintra.c and rdopt.c files in the VP8 source tree.

  
  

  Yaowu Xu, Ph.D. is a codec engineer at Google.

  
  

  

• Inside WebM Technology : VP8 Intra and Inter Prediction

  20 juillet 2010, par noreply@blogger.com (Lou Quillio)
  Continuing our series on WebM technology, I will discuss the use of prediction methods in the VP8 video codec, with special attention to the TM_PRED and SPLITMV modes, which are unique to VP8.

  
  

  First, some background. To encode a video frame, block-based codecs such as VP8 first divide the frame into smaller segments called macroblocks. Within each macroblock, the encoder can predict redundant motion and color information based on previously processed blocks. The redundant data can be subtracted from the block, resulting in more efficient compression.

  
  Image by Fido Factor, licensed under Creative Commons Attribution License.
  Based on a work at www.flickr.com

  
  

  A VP8 encoder uses two classes of prediction :

  • Intra prediction uses data within a single video frame
  • Inter prediction uses data from previously encoded frames

  The residual signal data is then encoded using other techniques, such as transform coding.

  
  

  VP8 Intra Prediction Modes

  VP8 intra prediction modes are used with three types of macroblocks :

  • 4x4 luma
  • 16x16 luma
  • 8x8 chroma

  Four common intra prediction modes are shared by these macroblocks :
  

  • H_PRED (horizontal prediction). Fills each column of the block with a copy of the left column, L.
  • V_PRED (vertical prediction). Fills each row of the block with a copy of the above row, A.
  • DC_PRED (DC prediction). Fills the block with a single value using the average of the pixels in the row above A and the column to the left of L.
  • TM_PRED (TrueMotion prediction). A mode that gets its name from a compression technique developed by On2 Technologies. In addition to the row A and column L, TM_PRED uses the pixel P above and to the left of the block. Horizontal differences between pixels in A (starting from P) are propagated using the pixels from L to start each row.

  For 4x4 luma blocks, there are six additional intra modes similar to V_PRED and H_PRED, but correspond to predicting pixels in different directions. These modes are outside the scope of this post, but if you want to learn more see the VP8 Bitstream Guide.

  
  

  As mentioned above, the TM_PRED mode is unique to VP8. The following figure uses an example 4x4 block of pixels to illustrate how the TM_PRED mode works :

  

  Where C, As and Ls represent reconstructed pixel values from previously coded blocks, and X₀₀ through X₃₃ represent predicted values for the current block. TM_PRED uses the following equation to calculate X_ij :

  
  

  X_ij = L_i + A_j - C (i, j=0, 1, 2, 3)

  
  

  Although the above example uses a 4x4 block, the TM_PRED mode for 8x8 and 16x16 blocks works in the same fashion.

  TM_PRED is one of the more frequently used intra prediction modes in VP8, and for common video sequences it is typically used by 20% to 45% of all blocks that are intra coded. Overall, together with other intra prediction modes, TM_PRED helps VP8 to achieve very good compression efficiency, especially for key frames, which can only use intra modes (key frames by their very nature cannot refer to previously encoded frames).

  
  

  VP8 Inter Prediction Modes

  
  

  In VP8, inter prediction modes are used only on inter frames (non-key frames). For any VP8 inter frame, there are typically three previously coded reference frames that can be used for prediction. A typical inter prediction block is constructed using a motion vector to copy a block from one of the three frames. The motion vector points to the location of a pixel block to be copied. In most video compression schemes, a good portion of the bits are spent on encoding motion vectors ; the portion can be especially large for video encoded at lower datarates.

  
  

  Like previous VPx codecs, VP8 encodes motion vectors very efficiently by reusing vectors from neighboring macroblocks (a macroblock includes one 16x16 luma block and two 8x8 chroma blocks). VP8 uses a similar strategy in the overall design of inter prediction modes. For example, the prediction modes "NEAREST" and "NEAR" make use of last and second-to-last, non-zero motion vectors from neighboring macroblocks. These inter prediction modes can be used in combination with any of the three different reference frames.

  
  

  In addition, VP8 has a very sophisticated, flexible inter prediction mode called SPLITMV. This mode was designed to enable flexible partitioning of a macroblock into sub-blocks to achieve better inter prediction. SPLITMV is very useful when objects within a macroblock have different motion characteristics. Within a macroblock coded using SPLITMV mode, each sub-block can have its own motion vector. Similar to the strategy of reusing motion vectors at the macroblock level, a sub-block can also use motion vectors from neighboring sub-blocks above or left to the current block. This strategy is very flexible and can effectively encode any shape of sub-macroblock partitioning, and does so efficiently. Here is an example of a macroblock with 16x16 luma pixels that is partitioned to 16 4x4 blocks :

  
  

  

  
  

  where New represents a 4x4 bock coded with a new motion vector, and Left and Above represent a 4x4 block coded using the motion vector from the left and above, respectively. This example effectively partitions the 16x16 macroblock into 3 different segments with 3 different motion vectors (represented below by 1, 2 and 3) :

  
  

  

  
  

  Through effective use of intra and inter prediction modes, WebM encoder implementations can achieve great compression quality on a wide range of source material. If you want to delve further into VP8 prediction modes, read the VP8 Bitstream Guide or examine the reconintra.c and rdopt.c files in the VP8 source tree.

  
  

  Yaowu Xu, Ph.D. is a codec engineer at Google.