AetherEngine 3.11.3

Fixed

Anamorphic SD content (DVD rips, widescreen DVDs) rendered "flattened" / horizontally squished (#23)

DVD MPEG-2 stores non-square pixels: NTSC 720x480 is encoded anamorphic for 4:3 display, and widescreen DVDs for 16:9. The software decode path (used for interlaced SD content, which has no hardware decoder) attached only color-space metadata to its output CVPixelBuffer and never the sample aspect ratio. CMVideoFormatDescriptionCreateForImageBuffer therefore produced a format description with no PixelAspectRatio extension, so AVSampleBufferDisplayLayer sized the picture with square pixels (a too-wide 3:2), squishing it horizontally.

The decoder now captures the container SAR at open() and attaches each frame's sample_aspect_ratio (with that stream-level fallback) as kCVImageBufferPixelAspectRatioKey, so the picture displays at its intended aspect (4:3 here, 16:9 for widescreen anamorphic DVDs). The native VideoToolbox path already reads SAR from the container, so only the software path needed this.

This is a follow-up to the 3.11.2 interlaced timing fix on the same issue. A regression test (DeinterlaceSARTests) pins that the deinterlacer forwards the source SAR to its output frames.

Thanks to @cstark27 for the report and verification.