IMX30 larger than XDCAM EX HD 35? at DVinfo.net

Gabor Heeres · March 17th, 2013, 02:47 AM

Hi All,

I've made an "IMX30 MXF preset" in Vegas, created from the original IMX50 preset and reducing the bitrate back to 30 Mbps. This is on request of one of my clients, broadcaster RTL here in the Netherlands. What wonders me though is that these files are significantly larger (in filesize) than those rendered out to the original 1920x1080 50i 35 Mbps XDCAM EX codec. So 30 Mbps SD footage is larger than 35 Mbps HD footage, that seems strange to me. From the same project o.c. Is this just a codec issue and should it be this way? Or am I missing something?

Thanks.

Gabor

Juris Lielpeteris · March 17th, 2013, 05:54 AM

Hi, Gabor.
IMX30 can be larger, because IMX MXF 30 has 30 Mbit constant video bitrate and allways contains 8 channels of audio (or free space for its). XDCAM EX HD 35 MXF has variable bitrate with maximum 35 Mbitps and average 25 Mbitps and may contains any number of audio channels.

March 17th, 2013, 02:47 AM	#1
Gabor Heeres Major Player Join Date: Jan 2009 Location: Eindhoven, The Netherlands Posts: 322	IMX30 larger than XDCAM EX HD 35? Hi All, I've made an "IMX30 MXF preset" in Vegas, created from the original IMX50 preset and reducing the bitrate back to 30 Mbps. This is on request of one of my clients, broadcaster RTL here in the Netherlands. What wonders me though is that these files are significantly larger (in filesize) than those rendered out to the original 1920x1080 50i 35 Mbps XDCAM EX codec. So 30 Mbps SD footage is larger than 35 Mbps HD footage, that seems strange to me. From the same project o.c. Is this just a codec issue and should it be this way? Or am I missing something? Thanks. Gabor

March 17th, 2013, 05:54 AM	#2
Juris Lielpeteris Major Player Join Date: Oct 2012 Location: Riga, Latvija, EU Posts: 292	Re: IMX30 larger than XDCAM EX HD 35? Hi, Gabor. IMX30 can be larger, because IMX MXF 30 has 30 Mbit constant video bitrate and allways contains 8 channels of audio (or free space for its). XDCAM EX HD 35 MXF has variable bitrate with maximum 35 Mbitps and average 25 Mbitps and may contains any number of audio channels.