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A Bit About Legendary German Animation

Saturday, August 5th, 2017

If you talk about German films as a foreigner you might know some good ones like influential Fritz Lang movies (for Frau im Mond they’ve hired Hermann Oberth himself and as the result their depiction of space travel looks much more realistic than modern Hollywood flics) or Gojko Miti? adventure features (the Eastern Westerns). But if you’re not from Germany, what German cartoons do you know? Looks like the only German cartoons that got some widespread action are those from Dingo Pictures.

Dingo Pictures is a company located in Taunus that has produced about thirty Hess(l)ich cartoons in the second half of 1990s. Some of those were completely unique and some were ripped off by D*sney and Don Bluth earlier.

Dingo Pictures has their own unique and easily recognizable style. But before I explain it, here are the eponymous animals in one of their cartoons:

So, Dingo Pictures was a pioneer, combining computer drawn animation with 2D drawn background (watercolours no less!). Also like the anime father, Osamu Tezuka, the company had a cast of actors always appearing in every cartoon.

For example:
The Bear (he often changes scenes and complains about everything)

Goldie (named so after the Austrian book Bambi) and Wuschel (the squirrel), Ringo the Hare is not pictured here

And here’s the star of all Dingo Pictures cartoons, the one and only Wabuu:
Wabuu!

In case you didn’t know, Wabuu was so popular that he had his own original cartoon, title song (that can be heard in several other cartoons too) and even audio books! Even now the DVD with his own cartoon costs at least twenty Euro on Amazon and about ten Euro used (for comparison, you can buy almost any other used DVD with Dingo Pictures cartoon for one eurocent).

Anyway, we were talking about the style. It’s hard to express in words what makes Dingo Pictures cartoons so charming but I think phrases “record-mending animation quality”, “copy-pasting everything”, “reusing the same scenes in other cartoons”, “more padding that Star Trek The Motionless Picture” and “dull voice acting” would do.

Here are some shots from one of their longer films, King of the Animals (or Lion King for short), don’t mind the quality, I tried to be lazy:

Title card. One of the best ones, honestly.

Every animal is uniquely redrawn.

The titular king.

Nice backgrounds.

One of moles (as you can guess from its look this mole is Italian).

The story is very typical: the lion rules the jungle full with monkeys, hippos, crocodiles and vultures (and with hares, squirrels and bears—the bear picture above is from this cartoon). One day a monkey finds diamonds but they decide not to mine them in fear of humans coming. With the birth of his son, the lion king loses interest in ruling and the black panther seizes the power with cheating and false promises and exiles the king. Later, with the help of snake, vultures and bear the panther is defeated. If you think you’ve heard this story elsewhere, don’t worry—it has unexpected twists in it.

And in the end we have scenes like this:
The vultures asked for a computer with phone and modem for their help.

The Black Panther is defeated!

BTW the snake enjoys reading books and quotes Shakespeare, Goethe, Karl Marx and Gorbachov. If you find this strange how could you get past the fact the panther’s name is Bocassa?

How one can not enjoy masterpieces like this! Oh, and every time I hear sirens I remember the duck from Animal Football, that’s how much their art has touched me.

There’s a sequel to it, simply called King of the Animals The Second Part but it’s of lesser quality IMO.

The other noteworthy cartoons are Aladdin(the genie there is a famous actor who is not Robin Williams), Animals Football(there they’ve copy-pasted all their animal characters and then some), Bremen Musicians(it has live narrator filmed, not just animation), The Case for Mouse Police(it simply needs to be seen to be believed) and of course Wabuu.

P.S. For some reason DVDs are distributed by P*wer Channel GmbH and don’t mention the original creator anywhere except in the video. They are that modest.

P.P.S. Honestly, I don’t think I’ve heard about any other German cartoons. But these cartoons have reviews in BaidUTube channels of people from countries like Canada and Sweden (the latter is in Swedish of course, actually Wabuu song sounds even better in Swedish than in German).

Posted in Dingo Pictures | 1 Comment »

#chemicalexperiments — Lasagne

Saturday, August 5th, 2017

Let me start with a bit of history.

Normal don’t care much how to eat their pasta—they simply cook it, add whatever they have (even mayo probably or nothing at all) and eat it. Italians are different, they select pasta sauce first and then decide what pasta will go fine with it. In case of meat sauce (or ragù as locals call it) Italians considered that wide plain pasta would go best with it for some reason. So they competed who can use the wider noodles and the guy who simply took the whole plates won. But it was a bit inconvenient to cook them and then mix with sauce so they’ve switched to oven baking the whole thing in sauce instead. And that’s how lasagne was born (probably; Italians have a completely different story to tell but they always do).

Since I’d better avoid meat entirely, I decided to cook my own version with various components (in several tries too) and here’s my short summary:

it’s better to use thick sauces;
tomato sauce is a definite must, it adds flavour;
cheese sauce is good mostly for the lowest layer (to lay lasagne plates on it) and for pouring on top;
ricotta and Quark make fine layers too, you can even mix them with some vegetables;
sliced boiled eggs would make a nice addition to a layer with tomato sauce;
mozzarella is better avoided since it will result in hard chewy chunks contrasting with the texture of the rest of the dish.

Overall, it’s nice dish, would bake again.

Posted in #chemicalexperiments | 2 Comments »

Rust: Optimising Decoder Experience

Thursday, August 3rd, 2017

Okay, I’ve made some changes so hopefully the server will withstand the curiosity of more than two people if it will go like the last time.

So, after implementing Indeo 4/5 decoders for NihAV I nano-benchmarked it and my decoder was about twice as slow compared to libavcodec. And since neither has SIMD optimisations they should be good enough to compare.

The tested file was 00186002.avi — Indeo 4 sample with scalability feature(i.e. luma is split into four bands and uses Haar wavelet to compose the output plane) and duration over ten minutes. The results I got will be given in Linux perf sample counts as those should be representative enough.

avconv — 13.4 seconds, 10K cycles. About 24% spent in luma plane recombination (with Haar wavelet), about 40% of time is taken by bitstream decoding and the rest is mostly transforms and motion compensation.

nihav-tool — 31.6 seconds, 20K cycles. 30% spend in luma plane recombination, 48% of time is taken by bitstream decoding, 11% is for motion compensation and the rest is mostly transforms. Or in samples: recombination — 9900 (against 3300 in libavcodec), bitstream decoding (dirty estimate, it includes some DSP functions inlined) — 15800 against
5600. Motion compensation — 3500 against 1700. Transforms — 1300 against 1500 (they are not equivalent though, my code only transforms the block and output costs are hidden in bitstream decoding). Overall, my code is consistently worse. Is there any way to optimise it a bit?
(more…)

Posted in NihAV, Rust, Useless Rants | 12 Comments »

Rust: Not So Great for Codec Implementing

Monday, July 31st, 2017

Disclaimer: obviously it’s my opinion, feel free to prove me wrong or just ignore.

Now I should qualify for zoidberg (slang name for lowly programmer in Rust who lives somewhere in a dumpster and who is also completely ignored—perfect definition for me) I want to express my thoughts about programming experience with Rust. After all, NihAV was restarted to find out how modern languages fare for my favourite task and there was about one language that was promising enough. So here’s a short rant about the aspects of this programming language that I found good and not so good.

Good things

Modern language features: standard library containers, generics, units and their visibility etc etc. And at least looks like Rust won’t degrade into metaprogramming language any time soon (that’s left for upcoming Rust+=1 programming language);
Reasonable encapsulation: I mean both (sub)modules organisation and the fact that functions can be implemented just for some structure;
Powerful enums that can act both as plain C set of values and also as tagged objects, e.g. the standard Result enum has two values—Ok(result) and Err(error) where both result and error are two different user-defined types, so returned value can contain either while being the same type (Result);
More helpful error messages (e.g. it tries to suggest a correction for mistyped variable name or explains an error a bit more detailed). Sure, Real Programmers™ don’t need that but it’s still nice;
No need for dependency resolving: you can have stuff in one module referencing stuff in another module and vice versa at the same time, same for no need
Traits (standard interfaces for objects) and the fact that operations are implemented as specific traits (i.e. if you need to have a + b with your custom object you can implement std::ops::Add for it and it will work). Also it’s nice to extend functionality of some object by making an implementation for some trait: e.g. my bitstream reader is defined in one place but in another module I made another trait for it for reading codebooks so I can invoke let val = bitread.read_codebook(&cb)?; later.

Unfortunately, it’s not all rosy and peachy, Rust has some things that irritate me. Some of them are following from the advantages (i.e. you pay for many features with compilation time) and other are coming from language design or implementation complexity.

Irritating things that can probably be fixed

Compilation time is too large IMO. While the similar code in Libav is recompiled in less than a second, NihAV (test configuration) is built in about ten seconds. And any time above five seconds is irritating to wait. I understand why it is so and I hope it will be improved in the future but for now it’s irritating;
And, on the similar note, benchmarks. While overall built-in testing capabilities in Rust are good (file it under good things too), the fact that benchmarking is available only for ~~limbo~~ nightly Rust is annoying;
No control over allocation. On one hoof I like that I can not worry about it, on the other hoof I’d like to have an ability to handle it.
Poor primitive types functionality. If you claim that Rust is systems programming language then you should care more about primitive types than just relying on as keyword. If you care about systems programming and safety you’d have at least one or two functions to convert type into a smaller one (e.g. i16/u16 -> u8) and/or check whether the result fits. That’s one of the main annoyances when writing codecs: you often have to convert result into byte with range clipping;
Macros system is lacking. It’s great for code but if you want to use macros to have more compact data representation—tough luck. For example, in Indeo3 codebooks have sequences like (a,b), (-a,-b), (b,a), (-b,-a) which would be nice to shorten with a macro. But the best solution I saw in Rust was to declare whole array in a macro using token tree manipulation for proper submacro expansion. And I fear it might be the similar story with implementing motion compensation functions where macros are used generate required functions for specific block sizes and operations (simple put or average). I’ve managed to work it around a bit in one case with lambdas but it might not work so well for more complex motion compensation functions;
Also the tuple assignments. I’d like to be able to assign multiple variables from a tuple but it’s not possible now. And maybe it would be nice to be able to declare several variables with one let;
There are many cases where compiler could do the stuff automatically. For example, I can’t take a pointer to const but if I declare another const as a pointer to the first one it works fine. In my opinion compiler should be able to generate an intermediate second constant (if needed) by itself. Same for function calling—why does bitread.seek(bitread.tell() - 42); fail borrow check while let pos = bitread.tell() - 42; bitread.seek(pos); doesn’t?
Borrow checker and arrays. Oh, borrow checker and arrays.

This is probably the main showstopper for implementing complex video codecs in Rust effectively. Rust is anti-FORTRAN in a sense that FORTRAN was all about arrays and could operate arrays safely while Rust safely prevents you from operating arrays.

Video codecs usually operate on planes and there you’d like to operate with different chunks of the frame buffer (or plane) at the same time. Rust does not allow you to mutably borrow parts of the same array even when it should be completely safe like let mut a = &mut arr[0..pivot]; let mut b = &mut arr[pivot..];. Don’t tell me about ChunksMut, it does not allow you to work with them both simultaneously. And don’t tell me about Bytes crate—it should not be a separate crate, it should be a core language functionality. In result I have to resort to using indices inside frame buffer and Rc<RefCell<...>> for frames themselves. And only dream about being able to invoke mem::swap(&mut arr[idx1], &arr[idx2]);.

Update: so there’s slice::split_at_mut() which does some of the things I want, thanks Tomas for pointing it out.

And it gets even more annoying when I try to initialise an array of codebooks for further user. The codebook structure does not implement Clone because there’s no good reason for it to be cloned or copied around, but when I initialise an array of them I cannot simply declare it and fill the contents in a loop, I have to resort to unsafe { arr = mem::uninitialized(); for i in 0..arr.len() { ptr::write(&arr[i], Codebook::new(...); } }. I know that if there’s an error creating new element compiler won’t be able to ensure that it drops only already initialised elements but it’s still a problem for compiler not being smart enough yet. Certain somebody had an idea of using generator to initialise arrays but I’m not sure even that will be implemented any time soon.

And speaking about cloning, why does compiler refuse to generate Clone trait for a structure that has a pointer to function?

And that’s why C is still the best language for systems programming—it still lets you to do what you mean (the problem is that most programmers don’t really know what they mean) without many magical incantations. Sure, it’s very good to have many common errors eliminated by design but when you can’t do basic things in a simple way then what it is good for?

Annoying things that cannot be fixed

type keyword. Since it’s a keyword it can’t be used as a variable name and many objects have type, you know. And it’s not always reasonable to give a longer name or rewrite using enum. Similar story with ref but I hardly ever need it for a variable name and ref_<something> works even better. Still, it would be better if language designers picked typedef instead of type;
Not being able to combine if let with some other condition (those nested conditions tend to accumulate rather fast);
Sometimes I fear that compilation time belongs to this category too.

Overall, Rust is not that bad and I’ll keep developing NihAV using it but keep in mind it’s still far from being perfect (maybe about as far as C but in a different direction).

P.S. I also find the phrase “rewrite in Rust” quite stupid. Rust seems to be significantly different from other languages, especially C, so while “Real Programmers can write FORTRAN program in any language” it’s better to use new language features to redesign interfaces and make new overall design instead of translating the same mistakes from the old code. That’s why NihAV will lurch where somebody might have stepped before but not necessarily using the existing roads.

Posted in Rust, Useless Rants | 15 Comments »

A Bit about Airlines

Tuesday, July 25th, 2017

I did not want to have personal rants in my restarted blog but sometimes material just comes and presents itself.

As some of you might know, I prefer travelling by rail; yet sometimes I travel by plane because it’s faster. Most of those flights are semiannual flights to Sweden and an occasional flight to elenril-city. And here’s the list of unpleasant things I had with flights:

Planes being late for more than an hour (because of technical reasons) — two Lufthansa flights from Arlanda;
Plane being late just because — Aerosvit, once;
Baggage not loaded on plane — Cimber Sterling (aka Danish Aerosvit);
Flights cancelled because of strike — once SAS and once Lufthansa;
Flight being cancelled because of plane malfunction — Lufthansa once;
Flight being cancelled because they didn’t want to wait for the passengers — Lufthansa once (yup, people were waiting at the gate but they decided to skip boarding entirely and send the plane away without passengers);
Flight where I could not check in — Lufthansa once.

To repeat myself, most flights I make during the year are with SAS to/from Sweden though sometimes segment is operated by LH. So far return trips to Frankfurt with LH were mostly okay except for some delays but the last “flight” was something different.

I booked a flight FRA-PRG-FRA. The flight to Praha was cancelled because plane arrived to Frankfurt at least half an hour later than expected and after another hour it was decided it’s not good enough to fly again. Okay. So they could not find a replacement plane and rebooked me to flight at 22:15. Fine, but it turned out that I could reach Praha by train faster and cheaper (twice as cheap actually) so I decided not to wait.

Then the time for return flight came and I could not check in at all because they have modified something (that’s the message: “Cannot check in to your flight because of modifications, refer to Lufthansa counter.” And there’s no LH representative there. And if you can withstand their call centre, you’re a much better person than I am). So it was another train back to Germany (which also broke down in the middle of nowhere but at least it was resolved in an hour and a half). Maybe it’s because of the selected Cattle Lowcostish fare (Economy but without check-in baggage or seat selection) instead of the usual one but at least with SAS when I wasn’t able to take flight to Arlanda (because of Frankfurt Airport staff strike) I still had no problems flying back from there.

Call me picky (and I shan’t argue, I am picky) but I expect better statistics because the most irritating cases were happening with the certain company that I don’t fly with often and that’s comparable with SAS in quantity (but, sadly, not quality).

And that means I’ll avoid using it in the future even if that means not being able to get to some places by plane in reasonable time. There are still trains for me.

P.S. This rant is just to vent off my anger and frustration from the recent experience. And it should make me remember not to take Air Allemagne flights ever again.
P.P.S. Hopefully the next post will be more technical.

Posted in Useless Rants | 1 Comment »

#chemicalexperiments — Cheese Cakes

Saturday, June 3rd, 2017

This is rather controversial topic because different countries recognize different kinds of cheese let alone what can be made out of it so what bears the name “cheese cake/pie” in one country might be not recognized as such in another.

So, cheese. Depending on country you have either one or two categories of cheese recognized: so called cottage cheese (or Quark/kvarg in Germanic language countries) and the rest of hard or semi-hard products made of milk. There’s also Italy where some cheeses (like mozzarella, provolone or scamorza) are considered to be pasta but that’s Italy and it doesn’t deserve second mention in this post.

Cottage cheese can be also divided into two categories: grainy and homogeneous mass. The first kind is more common in Eastern Europe (I’ve seen it in Ukraine, Czechia and Hungary for example; it can be also found in Germany but only in rather small packaging and runny), the second kind is more common in Germany.

The conventional hard or semi-hard cheese can be made into a pie usually by grating it, mixing with cream and eggs or sour cream and baking.

And of course there’s USA where what they call cheesecake is made (if you believe Wickedpedia) from either cream cheese (i.e. product where cheese-making process was terminated halfway) or ricotta (made from whey instead of milk, so not a cheese either).

Now, let’s look at real cheese cakes/pies I’ve encountered so far or even made myself:

Ukraine — there’s a traditional Ukrainian dish сирники, patties made from grainy cottage cheese mixed with semolina or millet and flour and fried. Those I like and approve;
Germany — there are two similar variation of what is called käsekuchen(literally cheese cake). In both cases it’s mostly Quark (homogeneous cottage cheese) mixed with semolina and baked, in one case they’re also made more cake-like by mixing milk and starch and adding pieces of tangerine. This variation I bake myself time from time, it goes even better with a bit of sour cream (Schmand) or gräddfil on top;
Switzerland — there they have Chäschueche(essentially käsekuchen pronounced in Swiss German) which is obviously nothing like its German counterpart. Instead we have a small tart made from local chäs(semi-hard semi-sticky Swiss cheese with stinky rind) that’s rather savoury instead of sweet. I’ve tried them once, found them edible but not something spectacular;
Sweden — this country has ostkaka(literally cheese cake) which can be described as an interesting cheese that was too good to wait for it so it was baked instead of ripening all the way. Obviously I buy it when possible and eat with lingon jam, there’s especially good version available in Jul season;
Sweden — there’s not enough of it! Sweden also offers västerbottensostpaj(or simply västerbottenpaj) which is a quiche-like pie with filling made from the best cheese in the world (from Burträsk obviously) combined with eggs and cream (I should try gräddfil instead) and baked. I enjoy them both in Sweden and sometimes bake it myself (when I have The Cheese) because it’s worth it.

And an the end several fun facts:

German name for cottage cheese (Quark) is most likely the one that got into Finnegans Wake, from which it was borrowed later for certain physical term (though physicists playing stringed models refuse to acknowledge that concept);
in Czechia grainy cottage cheese (tvaroh) is sold in pressed triangles, if you wrap a cabbage leaf around it you can troll Japanophiles that it’s local onigiri (like I did once);
in Sweden they actually have different names for grainy cottage cheese (called “cottage cheese”) and homogeneous one (called “kvarg”);
and in Ukraine it’s all called simply “cheese” (maybe because hard cheese was not common in Ukraine, only hard cheese-like product sold in Soviet times);
another fun fact from Ukraine—cottage cheese sold on markets by individuals varies in units depending on region: in some places it’s sold by weight, in some places it’s sold by volume (using standard half-litre jars for example), in some places it’s sold by saucers (i.e. how much of it you can put on a saucer) and in other places it’s sold by amount yielded from 3 litres of milk.

Okay, back to doing nothing.

Posted in #chemicalexperiments | Comments Closed

#chemicalexperiments

Friday, May 19th, 2017

Well, here’s yet another post nobody asked.

As a bog standard programmer I love organ music, hacking various stuff, and cooking Also it’s easier to satisfy my tastes and limitations that way too.

I’m not a skilled cook at all but I can make myself a semi-decent soup or bake something (casserole, quiche or pie). And here’s my short report on trying macaroni and cheese in three variations.

The first version was made after some recipe—cook pasta (I chose fusilli because it’s the only kind I had at hoof), make cheese sauce (essentially start with sauce thickener made from fried flour, add milk and melt a lot of cheese in it), combine together and bake in oven. Simple, filling and tasty. The only problem I found is that it thickens into a solid mass when cooled but it’s still enjoyable then.

The second version I tried was Kraft dinner. Just cook the pasta from the box and mix it with milk, butter and powder (from the packet inside the box) in still warm cooking pot. This version I found incompatible with me—not gross or allergy inducing, just after tasting one spoonful I could not bring myself to take another. Oh well, not a big loss.

And finally, käsespätzle. For this variation you take spätzle (the usual long thin variation sold in every supermarket here), mix it with cooking cream that has been boiled and with some cheese melted it, put the result into baking dish, sprinkle with more grated cheese and bake (I’ve also added chopped dried tomatoes because I had to put them somewhere). The result is tasty and more tender than the first variation. So I approve it too.

P.S. I don’t take pictures of what I cook, you want #opticalexperiments then and from a different person too.

Posted in #chemicalexperiments | 4 Comments »

Why Modern Video Codecs Suck and Will Keep on Sucking

Friday, May 12th, 2017

If you look at the modern video codecs you’ll spot one problem: they get designed for large resolutions and follow one-size-does-not-fit-exactly-anybody approach. By that I mean that codecs are following the model introduced by ITU H.261—split image into blocks, predict block from the previous frame if possible, apply DCT, quantise and code resulting coefficients (using zigzag scan order and special treatment for runs of zeroes). The same was later applied to pictures in JPEG format that is still staying strong.

Of course modern codecs are much more complex that that, current ITU H.EVC standard enhanced every stage:

image is no longer split into 8×8 blocks, you have quadtrees coding blocks from 64×64 down to 4×4 pixels;
block prediction got more complicated, now you have intra (or spatial prediction) that tries to fill block with gradient derived from already decoded neighbour blocks) and inter prediction (the old prediction from the previous frame);
and obviously inter prediction is not that simple either: now it’s decoupled from transformed block and can have completely different sizes (like 16×4 or 24×32), instead of single previous frame you can use two reference frames selected from two separate lists of references and even motion vectors are often predicted using motion vectors from the reference frames (does anybody like implementing those colocated MV prediction modes BTW?);
DCT is replaced with some bitexact integer approximations (and the dequantisation and/or transform stages may be skipped completely);
there are more scan types used and all values are coded using some context-adaptive coder.

Plus some hacks for low-resolution mode (e.g. special 4×4 transform for luma), lossless (or as they call it, “PCM coding”) and now also special coding mode for screen content (i.e. images with fewer distinct colours and where fine details matter).

The enhancements on streamline coding process are enhancements, they don’t change principles of coding but rather adapt them to modern conditions (meaning that there’s demand in higher compression and there’s more CPU power and RAM can be thrown at the processing—mostly RAM though).

And what the hacks do? They try to deal with the fact that this model works fine for smooth changing continuous tone images and it does not work that good on other types of video source. There are several ways to deal with the problem but keep in mind that the problem of distinguishing video types and selecting proper coding is AI-complete:

JPEG+PNG approach. You select best coder for the source manually and transmit it like that. Obviously it works well in limited scenarios but even people quite often don’t bother and compress everything with the single format even if that hurts quality or compression ratio. Plus you need to handle two different formats, make sure that the receiving end also supports them etc etc.
MPEG-4 approach. You have single format that has various “coding tools” embedded, they can be both full alternative coding features (like WebP has VP8 compression and lossless compression and nothing common between them or MPEG-4 Audio can be coded as conventional AAC, TwinVQ, speech codec or even as a description for synthesised audio) or various enhancement applied to the main coding method (like you have AAC-LC, AAC-Main that enables several features or HE-AACv2 which takes AAC-LC audio and applies SBR and Parametric Stereo to double its channels and frequency range). Actually there are more than forty various MPEG-4 Audio object types (various coding modes) already, do you think there’s any software that supports everything? And looks like modern video codecs head this way too: they introduce various coding tools (like for screen content) and it would be fun to support all possible features in the decoder. Please consider how much effort should be spent on effectively applying all those tools too (and that’s obviously beside the scope of standards).
ZPAQ approach. The terminal AI-complete solution. You are not merely generating bitstream but first you need to transmit bytecode for a program that will decode this bytestream. It’s the ultimate solution—if you can describe the perfect model for the stream then you can compress it the best. Finding an optimal model for given bitstream is left as an exercise for the reader (in TAoCP it would be marked with M60 I guess).

The second thing I find sucky is combinatorial explosion of encoding parameters. Back in the day you had to worry about selecting the best quantisation matrix (or merely a quantiser) and motion vector if you decided to code it as inter-block. Now you have countless ways to split large tile into smaller blocks, many ways to select prediction mode (inter/intra, prediction angle for intra, partitioning, reference frames and motion vectors) and whether to skip transform stage or not and if not whether it’s worth to subdivide block further or not… The result is as good as string theory—you can get a good one if you can guess zillions of parameters right.

It would be nice to have encoder actually splitting video into scene and actors and transmitting just the changes to the objects (actors, scene) instead of blocks. But then you have a problem of coding those descriptions efficiently and even greater problem of automatically classifying the video into such objects (obviously software can do that, that’s why MPEG-4 Synthetic Video is such a great success). Actually it had some use: there was AVS-S standard for coding video specifically from surveillance cameras (why would China need such standard anyway?). In this standard there was special kind of frame for the whole scene and the main share of video was supposed to be just objects moving around the scene. Even if the standard is obsolete its legacy was included into ~~HEVS~~AVS2 as three or four new special frame types.

Personally I believe that current video formats are being optimised to local minimum, there are probably other coding methods that give larger gain on certain kinds of data, preferably with less tweaking. For example, that was probably the best thing about Daala, its PVQ coding; the rest was nor crazy enough. I have a gut feeling that vector quantisation might be a good base for an alternative approach to building video codecs. And I think it’s better to have different formats oriented for e.g. low-latency broadcasting and video distributing. If you remember, back in the days people actually spent time to decide which segment was coded better with DivX ;-) 3 Fast-Motion or DivX ;-) 3 Low-Motion, so those who care will be able to select proper format. And the rest can keep watching content in VP11/AV2 format. Probably only the last sentence will come to life.

That’s why I don’t expect bright future in video codecs and that’s why my blog is titled like this.

Posted in Useless Rants, Various Video Codecs | 4 Comments »

NihAV Development Progress

Saturday, May 6th, 2017

After long considerations and much hesitation NihAV finally accepts its first developer (that would be me). And for a change it will be written in Rust. First, it’s an interesting language worth learning; second, it seems to offer needed functionality without much hassle; third, it offers new features that are tempting to try. By new features I mostly mean enums, traits and functions bound to structures.

Previously I expressed the intent to do a completely new design of multimedia (mostly decoding) framework with decoders being assembled from smaller blocks. For example, if I’d implement VIVO H.263 decoder (just as a troll) it would contain these bits:

generic 8×8 block decoder interface that does common stuff for such decoders (maintaining block indices, filling frame information e.g. block type, motion vectors etc etc);
trait for 8×8 block decoder implementation that does actual bitstream decoding (functions for decoding GOP/picture/slice headers, MV prediction, block data decoding and such);
IPB frame shuffler as implementation of generic frame shuffler (i.e. that piece of code that selects which frames to use as references and which frame to output after decoding the current one);
maybe even custom codebook accessor (the piece of code that tells codebook generator what is the code and symbol at position N) so it doesn’t need to be converted into some fixed form.

There’s not much code written yet but there are some bits implemented: rudimentary universal bitstream reader, bytestream reader (the same for memory and file I/O) and semi-working framework for demuxing. That’s a start at least.

Side rant: it seems that visible languages (i.e. not completely obscure ones) that use := form assignment have rather unpleasant evangelists (full of themselves in the best case, actively pushing their language to replace everything else in the worst case). That includes Go, Oberon and Wolfram Language. I don’t mean that other languages are free of that problem but in these cases looks like the majority of posts or articles about such language are written from this position.

Posted in NihAV, Useless Rants | 2 Comments »

Blog Restarted

Saturday, May 6th, 2017

As you (imaginary person who actually read this blog) I’ve stopped blogging last year. Mostly I did it because I ran out of material to write about. Well, now I have some new thoughts that I’d rather dump on the blog and forget so the blog restarted.

While the previous blog was mostly centred on codec reverse engineering and design and rants about random topics, this version should be more about NihAV development and codecs design. And obviously useless rants on random topics—except on opensource multimedia projects (I’ve said enough about CEmpeg, Libav and such; corporate ones I might still have something about).

Let’s see how well it goes this time…

Posted in Useless Rants | 3 Comments »

Kostya's Boring Codec World