DCI Specs - Digital Cinema Initiatives

8.2.2.3. Alternative ContentThe projector is required to not preclude the ability to present alternative content. Theprojector can also provide an auxiliary content input.8.2.2.4. Single LensThe projection system is required to provide either a single lens solution or anunattended changeover if more than one lens is required.8.2.2.5. Color Space ConversionThe projection system is required to convert the incoming DCDM* color space to itsnative color space.8.2.2.6. Pixel CountThe sampling structure of the displayed picture array (pixel count of the projector) isrequired to be equal to or greater than that of the specified image containers (either4096 x 2160 or 2048 x 1080).8.2.2.7. Spatial Resolution ConversionThe projector is required to display either a native resolution of 4096x2160 or2048x1080. If the projector's native resolution is 4096x2160, and the incoming spatialresolution of the content is 2048x1080, then the projection system is required to performthe up-conversion of 2048x1080 content to 4096x2160. All spatial conversions arerequired to be done at an exact ratio of 2:1 in each axis, i.e., a projector with a horizontalpixel count of slightly higher than the image container is required to not convert theprojected image beyond the image container to fill the array, nor is an image to beconverted to something less than the 4096x2160 or 2048x1080 image container size.Should electronic image resizing or scaling be used to support a constant heightprojection or constant width projection theater environment, then it is required that theimage resizing or scaling does not introduce visible image artifacts. It is intended that theprojector project the full horizontal pixel count or the full vertical pixel count of the imagecontainer.8.2.2.8. Refresh RateIf the incoming frame rate is not the projection system native refresh rate, then theprojector is required to convert it to its native refresh rate.8.2.2.9. Forensic MarkingA Forensic Mark is required to be inserted in real time into the content at the earliestpoint after decryption and prior to the content data being present on any data busoutside the Media Block (see Section 9.4.6.1 Forensic Marking).8.2.2.10. Media BlockIn the preferred implementation, the projector is required to provide an area for a MediaBlock to be installed. If the Media Block is installed external to the projector, then a linkencrypted interface is required to ensure that no Digital Cinema content is in the clear.DCI Digital Cinema System Specification v.1.2 Page 80