Welcome from me too, @ktgw0316 ! Good luck with the project too. I need to find out more about it!
2 Likes
This is great news.
Welcome Masahiro!
1 Like
As far as I understood the history of Lightzone, the original authors have lately vanished and didn’t answer any email, and let the domain go. I’m glad @ktgw0316 forked the project and started bug fixing. I found his Release only beginning this year 2022. Sadly the executable was half working on my mac (Monterey). It starts, but misses a lot of icons, Photo refresh is laggy and tiles are missing. Well, I guess there is a lot to do 
By the way there is another (not that old) fork of Lighzone where @ktgw0316 is also participating. I suppose we should also invite Aries85 ? GitHub - Aries85/LightZone: LightZone is a photo editor for Mac, Windows, and Linux.
Great news @patdavid ! I used this interesting converter several times in the past. It seems to have involved since then 
Welcome @ktgw0316 ! Nice to see this software still being in development!
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@patdavid, just thinking if it might be an idea to edit the post where you mention the category to remove the www.lightzoneproject.org to stop people from clicking on the link - if they haven’t read the posts they won’t know they should go there any more with that site being defunct.
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With this new thread here, I’ll share from the thread I originally posted on a couple of post that I find relevant for those unfamiliar with LZ. Also, I found that Lightzone had a presence on Twitter and while inactive for some time, it is still there. Here are the post that may be helpful:
Old Forum on Wayback Machine
YouTube Tutorials
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Done! The old category description was still cached for some reason. I’ve also modified your post to use backticks ` around the url to avoid the auto-link. Thanks!
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No problem - thanks for the quick fix!
I’ve known it for a long time and sometimes I’ve tried to use it even if I’ve never looked into it.
Welcome.
glad to be here and know that LZ is still alive!
regards,
sattva
1 Like
Hello Masahiro Kitagawa,
Hope all is well. Writing in to check for any updates on the LightZone program?
Kind regards,
Sattva
Looking at the Git, not much going on except a new pull request, see: upgrade to SIMDe 0.7.4 by Mr-C Michael R. Carusoe (lives in Germany)
Sorry to have been quiet for a while. I had been very busy with other projects until recently.
I’m working on migration to LibRaw to support more cameras, but it’s harder than I expected.
I hope to be able to release new version of LightZone by end of June.
6 Likes
Great news! This should be top priority as DCRaw hasn’t been updated since 2018 and lagging far behind virtually all mirrorless cameras, and all Canon CR3 cameras. For those unfamiliar with LibRaw, it looks extremely promising and would be a fantastic upgrade to Lightzone. I didn’t get as far as trying to compile the source code yet, and I’m not so sure I have that capability. It looks like Windows is already compiled. I haven’t tested that yet either since I primarily use a Ubuntu 22.04 desktop.
Hello,
I have 0 real-life experience with low-level optimisation (I normally work as a business developer, so asynchronous execution and SQL tuning are the most often used methods to speed up our processes).
Have you perhaps already looked into the new Vector API to replace JNI and native code? It’s currently in incubation.
https://openjdk.org/jeps/438
To calculate a Eucledian norm using vectorised operations, one could write:
// the CPU-specific vectorisation params
private static final VectorSpecies<Float> SPECIES = FloatVector.SPECIES_PREFERRED;
static float[] vectorisedNorm(float[] x, float[] y, float[] z) {
float[] norm = new float[x.length];
int loopBound = SPECIES.loopBound(x.length);
int vectorSize = SPECIES.length();
int i;
for (i = 0; i < loopBound; i += vectorSize) {
FloatVector xVector = FloatVector.fromArray(SPECIES, x, i);
FloatVector yVector = FloatVector.fromArray(SPECIES, y, i);
FloatVector zVector = FloatVector.fromArray(SPECIES, z, i);
xVector.fma(xVector, yVector.fma(yVector, zVector.mul(zVector)))
.sqrt()
.intoArray(norm, i);
}
// process the remaining few items sequentially
for (; i < x.length; i++) {
norm[i] = (float) Math.sqrt(x[i] * x[i] + y[i] * y[i] + z[i] * z[i]);
}
return norm;
}
For very simple operations, auto-vectorisation is already very fast (in fact, the gain from the code above is minimal: with about 13 million entries in the arrays (6123 * 2123, to get some non-aligned items), I get 12 ms of computation time on my Ryzen 5 5600X); for more complex ones, and surely in experienced hands, the API could produce better results.
Also, allocating float[] norm for each test takes about 3 ms (as you know, Java will zero out the array, even though it is then completely overwritten by the calculation). Moving to an externally provided array, the time is about 9 ms instead of 12. Maybe using a MemorySegment could help; or simply organising the code in such a way that the array is reusable can eliminate that cost.
Parallelism via parallel streams and/or hand-written parallel code could also increase performance, though doing that on such short calculations as the sample shown above may not bring much benefit:
private static final ForkJoinPool POOL = new ForkJoinPool();
static float[] vectorisedNormPar(float[] x, float[] y, float[] z) {
float[] norm = new float[x.length];
int nCores = Runtime.getRuntime().availableProcessors();
int blockSize = SPECIES.loopBound(x.length / nCores);
POOL.submit(() ->
IntStream.range(0, nCores).parallel().forEach(blockN -> {
boolean isLastBlock = (blockN == nCores - 1);
int startIndex = blockN * blockSize;
processBlock(x, y, z, norm, startIndex, blockSize, isLastBlock);
})
).join();
return norm;
}
private static void processBlock(
float[] x, float[] y, float[] z, float[] norm,
int start, int blockSize, boolean isLastBlock) {
int end = isLastBlock ? SPECIES.loopBound(x.length) : start + blockSize;
int chunkSize = SPECIES.length();
int i;
for (i = start; i < end; i += chunkSize) {
FloatVector xVector = FloatVector.fromArray(SPECIES, x, i);
FloatVector yVector = FloatVector.fromArray(SPECIES, y, i);
FloatVector zVector = FloatVector.fromArray(SPECIES, z, i);
xVector.fma(xVector, yVector.fma(yVector, zVector.mul(zVector)))
.sqrt()
.intoArray(norm, i);
}
if (isLastBlock) {
for (; i < x.length; i++) {
norm[i] = (float) Math.sqrt(x[i] * x[i] + y[i] * y[i] + z[i] * z[i]);
}
}
}
This saves a little bit of time, but not much, I get about 11.4 ms/op on my 12-core CPU (probably memory/cache issues? I’m not a low-level guy).
On my machine, processing a block of 1024x1024 with 64 chunks (instead of nCores = Runtime.getRuntime().availableProcessors() above) gives the best results: 0.042 ns / vector (so I allocated the x, y and z arrays with a size of 1024x1024, passed them to the vectorisedNormPar method, and replaced nCores with the chunk size of 64, then ran vectorisedNormParallel(x, y, z, norm, 64) 10˙000 times, and divided the measured time (422 ms) by (10˙000 * 1˙024 * 1˙024).
.
Also, the Tornado VM promises GPGPU support (OpenCL, CUDA) through annotations:
class Compute {
public static void matrixMultiplication(final float[] A, final float[] B, final float[] C, final int size) {
for (@Parallel int i = 0; i < size; i++) {
for (@Parallel int j = 0; j < size; j++) {
float sum = 0.0f;
for (int k = 0; k < size; k++)
sum += A[(i * size) + k] * B[(k * size) + j];
C[(i * size) + j] = sum;
}
}
}
}
https://www.infoq.com/articles/tornadovm-java-gpu-fpga/
https://www.infoq.com/articles/java-performance-tornadovm/
2 Likes
Thank you for the update Masahiro! Appreciate your effort towards LightZone development!
Regards,
Sattva
Hi, I’ve just released new beta version of LightZone.
Please note that this is a beta version, so it may not be as stable as you expected.
- This version cannot open/edit Canon
.cr3files, since migration to LibRaw is still ongoing. - On macOS it crashes complaining about code signing. I’m working on this issue now. I’ll release fixed packages asap.
- If you cannot open your raw file that can be opened with older versions, please let me know your camera model shown on Metadata tab.
- Edit: If you are Fujifilm user, please don’t use this version. It cannot open Fujifilm raws because of a bug.
As for the migration to LibRaw, I can already open raw files with LibRaw on developing version of LZ, but resulting image color is greenish. I’m going to fix the color balance and enable the LibRaw in next release (5.0.0beta2).
7 Likes
Hi
I’ve only just discovered Lightzone and it’s impressive and quite simple to use. It really should be more widely known.
However I can’t find a way of increasing the size of the tools on a large high definition monitor - they need to be up to twice as big, and it would be good to be able give it more RAM.
Once I know how to make the tools the right size I’m looking forward to really getting to grips with it.
I have no answer for you even though I did use LZ on Windows back in the day when it was payware and Uwe Steinmüller was their photographic advisor. He died about ten years ago, but I just found that parts of his Outback Photo website still work: http://www.outbackphoto.com/content/technique.html
If I remember this correctly, the LZ programmer suddenly left the building. LZ entered a zombie state for quite some time while a group of LZ enthusiast users worked hard to move the code to Open Source. I believe the main obstacles were of legal nature as LZ depended on third party closed source code (libraries). Once solved, it was still an uphill battle as LZ needed programmers. Luckily, Masahiro Kitagawa showed up.
1 Like
The question I have is how is the software going to solve a large high definition monitor and small monitors that are not high def? Isn’t it easier to satisfy the larger group, presumably the other monitors? Further, can you modify your screen settings to match the settings of LZ? I noticed that you asked the same question on GitHub, but I didn’t have a chance to answer there yet.
Steve