A new version of PTGui will be released soon, and you can download a beta version already.
This beta version is now being tested but may still be unstable. If you
don't encounter problems with PTGui 9.1.9, it is better to wait for the next
The current stitching engine in PTGui started life at a time when most PCs were still running on a single processor
and graphics cards were only used to display things on a screen. But in the past few years computers have
become more powerful by increasing the number of processor cores, and these days the graphics card (GPU)
can be used not only for display but for general computing as well.
A GPU is an extremely powerful processor with many hundreds of processor cores, but software has to be rewritten
to be able to use that power.
That's exactly what's new in the PTGui 10 beta: a new stitching engine, rewritten from scratch to get the best performance
on modern hardware. For GPU processing the stitcher uses OpenCL, a technology supported by both major GPU vendors
(NVIDIA and AMD) and supported on Windows and Mac. Of course stitching without using the graphics card remains possible,
and CPU stitching performance has been improved as well. The new stitcher also uses significantly less memory, which speeds up
stitching of large gigapixel panoramas in particular.
The goal for the new stitching engine is to be fully compatible with the current stitcher; changes are entirely under the hood and the only difference you
should notice is a reduction in stitching time.
So how much speedup should you expect compared with PTGui 9? This depends on many factors
such as the GPU's processing power versus the CPU speed, how much time is spent writing the results to the disk, etc. Initial
tests suggest a speedup anywhere between 1.5x and 10x depending on hardware and on the kind of panorama.
But to give one benchmark as an example: the
Gigapixel Panorama Speedtest
on a particular machine
(6 core Intel i7, Windows 8.1, 32GB of RAM, AMD Radeon HD7870, Samsung SSD) stitches in 35 seconds, compared to
151 seconds in PTGui 9.1.9.
In this beta version the new engine is used only when stitching the final panorama.
But we plan to use it to accelerate other parts of PTGui as well, such as the
Panorama Editor, Detail Viewer and Publish to Website.
New tone mapper
The other change in PTGui 10 beta is a new tone mapping algorithm for HDR panoramas. The new algorithm gives natural looking results,
comparable in quality to Exposure Fusion. It's easy to use and much faster than the previous algorithm, which could take a very long time
for large panoramas.
To use the GPU for stitching a video card supporting OpenCL 1.1 is required, with a minimum of 512 MB video RAM. Every recent GPU
from AMD and NVIDIA should work.
At least 2 GB of video RAM is recommended: although the panorama doesn't need to fit entirely in the video RAM, moving data
between the CPU and the GPU is relatively slow and should be avoided to get the best performance.
Laptops have less powerful 'mobile' GPU variants to keep down power consumption, and many laptops only have integrated graphics.
On a laptop with discrete GPU the new stitcher
will run somewhat faster on the GPU than on the CPU, but the difference is not extreme. Integrated graphics are not supported at all (and would be slower anyway).
But Windows desktops can easily be upgraded with a new GPU, and adding a $300 GPU (like the HD7870 from the above benchmark)
will result in a significant speedup.
On Mac upgrading a GPU is mostly impossible: only the previous generation Mac Pro has replacable graphics hardware.
iMacs only have mobile class GPUs or integrated graphics. The new Mac Pro on the other hand has been designed with GPU
computing in mind and will be an ideal machine for running PTGui (even though PTGui currently only uses 1 of the 2 GPUs).
On a Mac PTGui requires OS X 10.9 (Mavericks) or later for GPU stitching.
Finally keep in mind that with this improvement in stitching speed, disk speed is actually becoming the limiting factor. Replacing a spinning hard disk
with an SSD will make even more difference than before.
Detailed list of changes
- Version 10.0beta3 (3 march 2014)
- Stability improvements. If this beta still crashes on your system please let us know on the support forum.
- More speed improvements, in particular for NVIDIA cards on Windows.
- PTGui will no longer attempt to use Intel integrated graphics for OpenCL. It's not supported currently due to apparent driver bugs, and it would be slower than using the CPU anyway.
- Fix: error 'openCL initialization failed' on macs with an AMD Radeon GPU
- Fix: PTGui crashed immediately upon startup on 64 bit Windows on certain processors
- Fix: Assert error 'lastBitmapfeedline <= lastpushabline' for True HDR panoramas
- Fix: PTGui used more GPU memory than configured in Options/Preferences. This could lead to out of memory errors (CL_MEM_OBJECT_ALLOCATION_FAILURE)
- Fix: Assert error if the panorama contained images outside the visible (or cropped) area
- Fix: when creating .exr files without alpha channel stripes could be seen in the otherwise 'transparent' parts of a panorama
- Fix: Assert error if Tonemap Preview was opened before all images were loaded
- Fix: Assert error in batch stitcher if a source image was not found
- Fix: in True HDR mode, grey patches would occur in areas that were overexposed in all of the brackets
- Fix: spherical equirectangular panoramas could have small horizontal streaks near the zenith or nadir
- Fix: grey bars when remapping an equirectangular panorama
- Fix: corrupted output or crashes for certain spherical panoramas
- Version 10.0beta2 (14 february 2014)
- fix: error 'CL_UNKNOWN_ERROR' immediately after launching PTGui on certain systems
- if PTGui crashes during 'initializing OpenCL' (for example due to GPU driver bugs), it will offer to disable GPU acceleration on the next launch
- fix: batch stitcher failed to run for projects containing masks ('assertion failed' error)
- fix: stitching raw images resulted in too dark output
- fix: mac: batch stitcher was launching hidden behind the main window
- fix: mac: batch stitcher would hang when closed
- Version 10.0beta1 (13 february 2014)
- GPU accelerated stitching using OpenCL
- New tone mapper
- New menu Images - Select: this allows for example to delete all images outside the visible area of the panorama. Or
in conjunction with the yellow crop lines in the panorama editor, to delete images any rectangular area of the panorama.
- Options/Preferences - Advanced: RAM usage is now specified as an absolute number of megabytes; previously this was set as
a percentage of available RAM
- Removed support for 16 bit linear HDR output: previously PTGui Pro could save HDR output in a 16 bit fixed point TIFF or PSD file.
This is no longer possible, HDR output is now 32 bit floating point or 16 bit half float EXR. Note that this was a rarely used feature,
and regular 16 bit output is still fully supported for low dynamic range and tone mapped output.
The following problems are known to exist in the current beta:
- Circular fisheye output projection does not give a circular image
- Smartblend and Enblend are not yet integrated in the stitcher, but will be supported in one of the following beta versions
- The new tone mapper may still show 'vortex' artifacts in nadir and zenith of spherical panoramas
- The new tone mapper by default is set to maximally boost the shadows, which will likely amplify image noise beyond acceptable levels.
A next version will analyze the histogram for suitable default settings. For now reduce the Boost Shadows slider until the noise is no longer visible.
- Stitching 32 bit .hdr and .exr images may result in blending artifacts
- LZW encoded TIFF output is relatively slow
- Documentation is not up to date yet
Since this is a beta version it may contain bugs; therefore your feedback is much appreciated.
Post any bugs, comments to the PTGui Google group
check the Known Issues list above before posting.
Installing multiple versions side by side
You can try the beta version without overwriting your existing copy of PTGui. On Windows select a different installation folder when prompted during installation
(e.g. C:\Program Files\PTGui Beta). On Mac the PTGui application can be copied from the install disk image, renamed, and installed in any
folder on your mac, not just the Applications folder.
If you have accidentally overwritten your copy of PTGui you can always download the former version again from this website.
Download PTGui or PTGui Pro, version 10.0beta3