HDMI Capture Using the Blackmagic Intensity Card

Background

CineForm supports real-time capture from HDMI sources directly into CineForm Intermediate files using the Blackmagic Intensity card within all of its products: Prospect, HD, Aspect HD and Connect HD.

HDMI has become entrenched as an output format from consumer video devices to display devices (TVs for instance).  It is also emerging as an output format for HD cameras, both consumer and professional.  Sony's new camera lineup includes HDMI output, and we used Sony's HVR-V1U for our development purposes.  Another intriguing fact about HDMI is that during live recording the HDMI output signal bypasses the camera's internal HDV (or AVCHD) recording format.  This means that the uncompressed HD signal is delivered over HDMI, and you can use an Intensity card with CineForm's Prospect HD, Aspect HD, or Connect HD to record directly into CineForm Intermediate files as the native camera acquisition format.  This has numerous advantage - both for resulting visual fidelity and also for your editing workflow.

From a specification standpoint, the HDMI interface also allows 10-bit data precision, although at present it appears that camera manufacturers are currently only supplying 8 bits as output through HDMI.  We will hope for future 10-bit data through HDMI.

Features

•  HDMI Sources: 1080i/p, 720p

•  CineForm Intermediate files:

-  Prospect HD: 1920x1080 YUV 4:2:2 10-bit
-  Aspect HD / Connect HD: 1440 x 1080 YUV 4:2:2 8-bit

•  (Optional) telecine removal for 1080p24 material embedded as 1080i60 (for instance for Sony's HVR-V1 and Canon's HV20). Resulting files are 24p (23.976) CineForm Intermediate for 24p editing workflow

Notes for using Decklink Intensity

First and foremost, it is imperative that the latest Intensity and Decklink components are installed. Blackmagic software and driver support is available here: http://www.blackmagic-design.com/support/software/.

Note that the HDMI source device should be plugged into the Intensity card and powered up before the PC is turned on.

Capture through Intensity is (currently) provided only in CineForm's HDLink utility that is located in the CineForm directory under Start --> All Programs.  To capture using HD Link with the Intensity card:

Select “Decklink Video Capture” from the device drop-down at the top of the window. 

Select the “Capture” tab.

Click the “Prefs” button to bring up the preferences window. 

a. Select a capture location and base capture name
b. Check “Up convert 8-bit to 10-bit”
c. Select desired quality.
d. Select the desired resize (none is preferable). 

For 60i capture select “Automatic” for Frame Format
For 30p capture select “Progressive” for Frame Format
For 24p capture select “Progressive” for Frame Format AND check “remove 3:2 pulldown” 

Click “OK” to close the Prefs window 

Click “Start” to begin capture.

Known issues

•  Currently the software assumes the source input is 1080i.  (If you're running the HVR-V1 in 24p mode it is still outputting 1080i over HDMI, so the 1080i setting is correct).
 
•  Sometimes the video and audio streams are not immediately delivered from the Decklink card, resulting in possible audio sync issues (1-5 frames out of sync) and the first few frames of the capture to show “No Video Input” text with Blackmagic logo.

PC Performance Requirements

We have the CPU performance of a few different PC/CPU configurations and the performance necessary to perform real-time capture using Intensity without dropping frames.  In general you need a dual core processor (Intel Core 2 Duo >2.33GHz works very well) to avoid dropping frames, or higher-end P4 CPUs such as the Pentium D 955/965 family.  Following are the results we have characterized - percentages are determined by observing the Windows CPU performance meter.

 Machine 24p 60i
 Dell Precision 390 (Intel Core 2 Duo 2.93 GHz) 40% 50%
 Gateway (Pentium D 965 - 3.73 GHz) 50% 60%
 Gateway (Pentium D 965 - 3.2 GHz) 60%  70%
 HP xw9300 (Dual Opteron 252) ("Old" by today's standards) 70%  80%

Feature Notes

We will continue adding additional features to new production release, including:

•  a monitor window during capture.  Currently you must monitor on your camcorder LCD or other external device.

•  additional capture mode formats. Current HDLink assumes the source input is 60i.  (Yes, this still works with the HVR-V1 in 24p mode.)  When in 24p mode the HVR-V1 outputs 24p telecined into 60i.  HDLink can remove the telecine in real time to perfectly recreate the original 24p signal and write a 24p CineForm Intermediate file to disk.

NOTE: At present CineForm software does not use the Intensity card to play out, nor can Intensity be used to monitor the editing timeline (using CineForm presets) in Adobe Premiere Pro.  We'll be investigating playback through Intensity in future software releases.  In the meantime, Intensity combined with Prospect HD/4K or NEO HD/4K is a great way to ingest footage originating through HDMI.

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