| Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum |
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| Websites across the world are increasing their use of the Portable Network |
| Graphics imaging format, as a powerful and cross-platform way to represent |
| images. With key features such as alpha blending, it is no surprise that many |
| websites in countries such as China and India also use larger high-resolution |
| PNG images on their sites. Increasingly these images are decoded by the mobile |
| device, and typically also scaled down to fit the user's zoom selection on the |
| device's browser. |
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| In order to improve the decode time, Qualcomm Innovation Center has optimized |
| the PNG library found on many common OS platforms such as Web OS, Android, and |
| Chrome OS. Our team re-implemented the png_read_filter_row() routine to utilize |
| the DSP-like SIMD capabilities of the ARM NEON instruction set. It was then |
| tuned for the specific VeNum hardware unit found as part of the CPU subsystem |
| of the Qualcomm Snapdragon platform. |
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| This resulted in a range of 0-50% improvement in PNG decode times. |