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File Format Specifications

HD Specifications

MPEG-2
Container:
Container Format: MPEG-PS (program stream)
File Extension: .mpg

Video Specs:
Compression Codec: MPEG-2
Screen Size: 1920×1080 (1080i)
Display Aspect Ratio: 16:9 (center-cut safe recommended)
Pixel Aspect Ratio: 1.0 (square pixels)
Scan Type: Interlaced, Top (Upper) Field First
Frame Rate: 29.97 fps (constant/fixed)
Frame Rate Mode: Drop Frame (DF)
Bit Rate: 35 Mb/s CBR (constant bit rate)

Audio Specs:
Audio Type: MPEG-1 Layer II
Channels: 2 channels (stereo)
Sample Rate: 48000 Hz
Bit Rate: 384 Kbps
See Additional Audio Options below.

Closed Captions:
CEA608 and CEA708 embedded in the video (ATSC DTVCC)
Please read the section about closed captions below.
MXF XDCAM
Container:
Container Format: MXF OP1a / XDCAM
File Extension: .mxf

Video Specs:
Compression Codec: XDCAM EX35 1080i60
File Extension: .mxf
Screen Size: 1920×1080
Display Aspect Ratio: 16:9 (center-cut safe recommended)
Pixel Aspect Ratio: 1.0 (square pixels)
Scan Type: Interlaced, Top Field First (Upper Field First)
Frame Rate: 29.97 fps (constant/fixed)
Frame Rate Mode: Drop Frame (DF)
Bit Rate: 35 Mb/s CBR (constant bit rate)

Audio Specs:
Audio Type: PCM
Channels: 2 channels (stereo)
Sample Rate: 48000 Hz
Bit Depth: 16 or 24
See Additional Audio Options below.

Closed Captions (if present):
CEA608 and CEA708 embedded as ancillary track (SMPTE 436M)
Please read the section about closed captions below.
If using Adobe Premiere, please use our MXF preset.
H.264
Container:
Container Format: Quicktime or MPEG-4
File Extension (if Quicktime): .mov
File Extension (if MPEG-4): .mp4

Video Specs:
Compression Codec: H.264
File Extension: .mov
Screen Size: 1920×1080 (1080p)
Display Aspect Ratio: 16:9 (center-cut safe recommended)
Pixel Aspect Ratio: 1.0 (square pixels)
Scan Type: Progressive
Frame Rate: 29.97 fps (constant/fixed)
Frame Rate Mode: Drop Frame (DF)
Format Profile/Level: Main or High (Main@L4.1 recommended)
Use B-Frames: Yes
Bit Rate: 30Mb/s
Scan Type: Progressive

Audio Specs (for Quicktime containers):
Audio Type: PCM (Little or Big Endian)
Channels: 2 channels (stereo)
Sample Rate: 48000 Hz
Bit Depth: 16 or 24
See Additional Audio Options below.

Audio Specs (for MPEG-4 containers):
Audio Type: AAC
Channels: 2 channels (stereo)
Sample Rate: 48000 Hz
Bit Rate: 256 Kbps
See Additional Audio Options below.

Closed Captions:
Please read the section about closed captions below.

SD Specifications

MPEG-2
Container:
Container Format: MPEG-PS (program stream)
File Extension: .mpg

Video Specs:
Screen Size: 720×480 (480i)
Screen Size, when VBI is present: 720×512 (512i)
Display Aspect Ratio: 4:3
Scan Type: Interlaced, Top (Upper) Field First
Frame Rate: 29.97 fps (constant/fixed)
Frame Rate Mode: Drop Frame (DF)
Bit Rate: 25 Mb/s CBR (constant bit rate)

Audio Specs:
Audio Type: MPEG-1 Layer II
2 Channel Stereo (Ch1, Ch2)
Sample Rate: 48000 Hz
Bit Rate: 384 Kbps
See Additional Audio Options below.

Closed Captions:
CEA608 CC1 on Line 21 (VBI)
Please read the section about closed captions below.
MXF IMX NTSC
Container:
Container Format: MXF
File Extension: .mxf

Video Specs:
Compression Codec: IMX30 NTSC, IMX40 NTSC, or IMX50 NTSC
Screen Size: 720×486
Display Aspect Ratio: 4:3
Scan Type: Progressive
Frame Rate: 29.97
Frame Rate Mode: Drop Frame (DF)
Format Profile/Level: Main or High (Main@L4.1 recommended)
Use B-Frames: Yes
Bit Rate: 15Mb/s

Audio Specs:
Audio Type: PCM
Audio Layout: 4 Mono Channels: Ch1=Left, Ch2=Right, Ch3=Silence, Ch4=Silence.
Bit Depth: 24 bit
Sample Rate: 48000 Hz
See Additional Audio Options below.

Closed Captions:
CEA608 CC1 on Line 21 (VBI)
Please read the section about closed captions below.
H.264
Container:
Container Format: Quicktime or MPEG-4
File Extension (if Quicktime): .mov
File Extension (if MPEG-4): .mp4

Video Specs:
Screen Size: 720×486
Display Aspect Ratio: 4:3
Pixel Aspect Ratio: D1/DV NTSC (0.9091)
Scan Type: Interlaced, Top (Upper) Field First
Frame Rate: 29.97 fps (constant/fixed)
Frame Rate Mode: Drop Frame (DF)
Bit Rate: 30 Mbps (IMX30), 40 Mbps (IMX40), 50 Mbps (IMX50)

Audio Specs (for Quicktime containers):
Audio Type: PCM (Little or Big Endian)
Channels: 2 channels (stereo)
Sample Rate: 48000 Hz
Bit Depth: 16 or 24
See Additional Audio Options below.

Audio Specs (for MPEG-4 containers):
Audio Type: AAC
Channels: 2 channels (stereo)
Sample Rate: 48000 Hz
Bit Rate: 256 Kbps
See Additional Audio Options below.

Closed Captions:
Please read the section about closed captions below.

Closed Captioning

High Definition (HD)
We recommend submitting files with embedded closed captioning in either the MPG container or the MXF container.
For MPG: CEA608/CEA708 embedded as ATSC DTVCC (line 9)
For MXF: CEA608/CEA708 embedded as ancillary data.
* CEA608 is required even for HD.

Standard Definition (SD)
SD files containing closed captioning must use the MPG container or the MXF container.
CEA608 closed captions must be inserted in the VBI (line 21).
Actual video screen size, including VBI, will be 720×512.
For MXF IMX, your software may describe screen size as 720×486, but actual screen size will be 720×512.

Some, but not all stations using Spotloader also accept embedded closed captioning in the Quicktime (MOV) or the MPEG-4 (MP4) container.


Additional Audio Options

All channels must be contained in one single multi-channel track.
Multiple mono tracks are also accepted.
Multiple tracks containing more than one channel per track are not accepted.

Stereo:
2 channels (L, R) — one stereo track or two mono tracks.

5.1 Surround (HD only):
6 channels (L, R, C, LFE, Ls, Rs) — one multi-channel track or multiple mono tracks.

Additional options, including SAP and “7/8 stereo pair” may also be accepted and are described under Audio Layouts