Keys and Compression

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Table of contents

Page's that link from here:

Notes

  • Compressed images often have artefacts due to a lack of chrominance information
  • This can be addressed using a blur (often just horizontal) on the hue and saturation channels of HLS colourspace
  • Shake comes with a tutorial on using different colour spaces to blur dv images before keying.
HDCAM
7.1:1 Compression and uses DCT compression with 8-bit, 3:1:1 colour sampling.
Fusion email list(external link) (cache) Although I have successfully pulled mattes from HDCAM recordings in the past, it is not for the faint of heart. The compression, the 8 bit recording, the somewhat compressed color space make it really tough, especially on blue (as opposed to green). The live HDSDI output on Sony HDCAM cameras and the Panasonic Varicam are *much* better quality when dumped to uncompressed disk or a superior recording format like D5. It's the onboard recording formats which, well, suck. by Bob Kertesz BlueScreen LLC (2005)
Fusion email list(external link) (cache) I pull keys off HDcam all the time.. One might try the same techniques for pulling Mattes from (Ahem)DV footages. One way to get rid of nasty jagged blocky keyed edges is to Convert rgb to yuv, blur the U and V only, reconvert to rgb then key. There's always good ol ROTO:) Greenscreen seems to work much better for most shots due to the YCbCr sampling compression keeping more of the green component. Also green is higher luminance than blue. by davedfx (2005)
HDCAM
7.1:1 Compression and uses DCT compression with 8-bit, 3:1:1 colour sampling.
Fusion email list(external link) (cache) Although I have successfully pulled mattes from HDCAM recordings in the past, it is not for the faint of heart. The compression, the 8 bit recording, the somewhat compressed color space make it really tough, especially on blue (as opposed to green). The live HDSDI output on Sony HDCAM cameras and the Panasonic Varicam are *much* better quality when dumped to uncompressed disk or a superior recording format like D5. It's the onboard recording formats which, well, suck. by Bob Kertesz BlueScreen LLC (2005)
Fusion email list(external link) (cache) I pull keys off HDcam all the time.. One might try the same techniques for pulling Mattes from (Ahem)DV footages. One way to get rid of nasty jagged blocky keyed edges is to Convert rgb to yuv, blur the U and V only, reconvert to rgb then key. There's always good ol ROTO:) Greenscreen seems to work much better for most shots due to the YCbCr sampling compression keeping more of the green component. Also green is higher luminance than blue. by davedfx (2005)
HDCAM
7.1:1 Compression and uses DCT compression with 8-bit, 3:1:1 colour sampling.
Fusion email list(external link) (cache) Although I have successfully pulled mattes from HDCAM recordings in the past, it is not for the faint of heart. The compression, the 8 bit recording, the somewhat compressed color space make it really tough, especially on blue (as opposed to green). The live HDSDI output on Sony HDCAM cameras and the Panasonic Varicam are *much* better quality when dumped to uncompressed disk or a superior recording format like D5. It's the onboard recording formats which, well, suck. by Bob Kertesz BlueScreen LLC (2005)
Fusion email list(external link) (cache) I pull keys off HDcam all the time.. One might try the same techniques for pulling Mattes from (Ahem)DV footages. One way to get rid of nasty jagged blocky keyed edges is to Convert rgb to yuv, blur the U and V only, reconvert to rgb then key. There's always good ol ROTO:) Greenscreen seems to work much better for most shots due to the YCbCr sampling compression keeping more of the green component. Also green is higher luminance than blue. by davedfx (2005)
HDCAM
7.1:1 Compression and uses DCT compression with 8-bit, 3:1:1 colour sampling.
Fusion email list(external link) (cache) Although I have successfully pulled mattes from HDCAM recordings in the past, it is not for the faint of heart. The compression, the 8 bit recording, the somewhat compressed color space make it really tough, especially on blue (as opposed to green). The live HDSDI output on Sony HDCAM cameras and the Panasonic Varicam are *much* better quality when dumped to uncompressed disk or a superior recording format like D5. It's the onboard recording formats which, well, suck. by Bob Kertesz BlueScreen LLC (2005)
Fusion email list(external link) (cache) I pull keys off HDcam all the time.. One might try the same techniques for pulling Mattes from (Ahem)DV footages. One way to get rid of nasty jagged blocky keyed edges is to Convert rgb to yuv, blur the U and V only, reconvert to rgb then key. There's always good ol ROTO:) Greenscreen seems to work much better for most shots due to the YCbCr sampling compression keeping more of the green component. Also green is higher luminance than blue. by davedfx (2005)
HDCAM
7.1:1 Compression and uses DCT compression with 8-bit, 3:1:1 colour sampling.
Fusion email list(external link) (cache) Although I have successfully pulled mattes from HDCAM recordings in the past, it is not for the faint of heart. The compression, the 8 bit recording, the somewhat compressed color space make it really tough, especially on blue (as opposed to green). The live HDSDI output on Sony HDCAM cameras and the Panasonic Varicam are *much* better quality when dumped to uncompressed disk or a superior recording format like D5. It's the onboard recording formats which, well, suck. by Bob Kertesz BlueScreen LLC (2005)
Fusion email list(external link) (cache) I pull keys off HDcam all the time.. One might try the same techniques for pulling Mattes from (Ahem)DV footages. One way to get rid of nasty jagged blocky keyed edges is to Convert rgb to yuv, blur the U and V only, reconvert to rgb then key. There's always good ol ROTO:) Greenscreen seems to work much better for most shots due to the YCbCr sampling compression keeping more of the green component. Also green is higher luminance than blue. by davedfx (2005)
HDCAM
7.1:1 Compression and uses DCT compression with 8-bit, 3:1:1 colour sampling.
Fusion email list(external link) (cache) Although I have successfully pulled mattes from HDCAM recordings in the past, it is not for the faint of heart. The compression, the 8 bit recording, the somewhat compressed color space make it really tough, especially on blue (as opposed to green). The live HDSDI output on Sony HDCAM cameras and the Panasonic Varicam are *much* better quality when dumped to uncompressed disk or a superior recording format like D5. It's the onboard recording formats which, well, suck. by Bob Kertesz BlueScreen LLC (2005)
Fusion email list(external link) (cache) I pull keys off HDcam all the time.. One might try the same techniques for pulling Mattes from (Ahem)DV footages. One way to get rid of nasty jagged blocky keyed edges is to Convert rgb to yuv, blur the U and V only, reconvert to rgb then key. There's always good ol ROTO:) Greenscreen seems to work much better for most shots due to the YCbCr sampling compression keeping more of the green component. Also green is higher luminance than blue. by davedfx (2005)

Created by ome. Last Modification: Sunday 04 of January, 2009 19:01:07 GMT by ome.
List of attached files
ID Name desc uploaded Size Downloads Actions
24 pdf 411_bluescreen.pdf dv.com DV keying Thu 14 of July, 2005 21:37 GMT by ome 274.05 Kb 2080 View Download