QC Test Reference
The tables below contain a list of all of the tests included with Qualify, and information about what each test does and how it can be configured.
File Checks
Check | Identifier | Description |
---|---|---|
File Bit Rate | FC-101 | Verifies that the calculated bit rate of the file (video audio bit rate/duration) falls within the defined Min/Max parameters. |
Duration | FC-102 | Checks that the duration of the file (video and audio) falls within the defined Min/Max parameters. |
Container Format | FC-103 | Verifies the 'wrapper' or container file used to hold the video and/or audio matches the user defined value. Examples would be 'TS' (MPEG-2 Transport Stream), 'MXF', 'MOV' etc. |
Size | FC-104 | Checks that the total file size falls within the Min/Max parameters. |
Container Start Timecode | FC-105 | Verifies that the Container Start Timecode matches the user specified value, with an adjustable tolerance. Can also optionally check for drop frame verification. |
Container End Timecode | FC-106 | Verifies that the Container End Timecode matches the user specified value, with an adjustable tolerance. Can also optionally check for drop frame verification |
Compare Stream Lengths | FC-108 | Checks whether the audio track is present throughout the duration of the video. An alert is raised if the audio track is shorter than the video track by more than 2 video frames. An alert is also raised if the audio track is found to be significantly longer (more than 2 seconds) than the video. |
Transport Stream Bit Rate | FC-109 | Check stream bitrate using PCRs which accounts for various stuffing methods. |
Container/Header Agrees With Essence | FC-112 | This is intended to be a general test to check that parameters which are potentially duplicated between container (systems layer) and essence (elementary stream) are consistent. |
Essence Start Timecode | FC-115 | Verifies that the Essence Start Timecode matches the user specified input, with an adjustable tolerance. Can also optionally check for drop frame verification. The material package start timecode can also optionally be compared against the GOP timecode. |
Essence End Timecode | FC-116 | Verifies that the Essence End Timecode matches the user specified input, with an adjustable tolerance. Can also optionally check for drop frame verification. |
Number of Tracks | FC-121 | Check the number of video, audio, subtitle and timecode tracks in the file. |
Container Drop Frame | FC-122 | Check that the container's start timecode is either drop-frame or non-drop as specified. |
Essence Drop Frame | FC-123 | Check that the essence's start timecode is either drop-frame or non-drop as specified. |
Dolby E Presence | FC-125 | Test for the presence of Dolby E. |
PID Versus Language | FC-127 | The Verification Unit compares the PID (Packet Identified in Transport Stream) versus the audio language ID coded in the PMT descriptor. The possible language codes are defined by ISO 639-2. |
Deep MXF Tests
Check | Identifier | Description |
---|---|---|
Deep MXF Tests | MX-101 | A range of in-depth MXF checks, to ensure technical conformance with a variety of MXF constraints. |
MXF Operational Pattern | MX-102 | Tests the Operational Pattern of an MXF file. Currently only OP-1a and Op-Atom are supported. |
AVC SPS/PPS | MX-103 | This test ensures that every frame of an AVC stream contains an SPS and PPS header. This is mandated by SMPTE RP2027. This test is only available when the 'Video Codec' test is enabled and set to 'H.264' and the 'Container' test is enabled and set to 'MXF'. |
Syntax Checks
Enabling syntax checking will test the appropriate codec based on the file provided.
Check | Identifier | Description |
---|---|---|
MPEG-2 Video Codec Syntax | SC-101 | For MPEG-2 streams, section 8.5 (Table 8-13) defines upper limits for bit rate, in Mbps, for each combination of Profile and Level. For MPEG-2 streams, section 8.5 (Table 8-14) of ISO/IEC 13818-2 defines the vbv_buffer size requirements (in bits) for each combination of Profile and Level. |
AVC/H.264/MPEG-4 Video Codec Syntax | SC-102 | Tests that the sequence should always start with an IDR picture as per ITU-T H.264. Sequences that start with a non-IDR picture can cause playability problems, including tearing, stuttering and freeze frames. Tests that bitstreams do not cause an underflow or overflow in the hypothetical reference decoder (HDR), as per ITU-T H.264, Annex C. Tests that PPS referenced in the headers exist in the file as per ITU-T H.264. Tests that bitstreams do not cause coded picture buffer (CPB) removal timing violations in the hypothetical reference decoder as per ITU-T H.264, Annex C. |
Dolby-E Audio Codec Syntax | SC-108 | CRC Check: Checks the CRC of each Dolby-E frame. Frames that fail the CRC check are likely corrupted either in transport or in the decoder. Guard Band Alignment: Checks Dolby-E guard band start position against the values from Table 4-2 of the Dolby-E specifications. Guard Band Not In Ideal Position: Checks for a Dolby-E frame that is not in the ideal position in reference Table 4-2 of the Dolby-E specifications. Frame Rate Coherency: Checks for a Dolby-E stream where the frame rate does not match with the container metadata frame rate. Frame Synchronization: Checks for a frame without a synchronization header in the Dolby-E stream. |
Caption / Subtitle Checks
Video Metadata
Check | Identifier | Description |
---|---|---|
Bit Depth | VM-101 | The number of bits per video sample. For cases where luma and chroma sample depths are different, this check will test the luma bit depth. |
Video Track ID/PID | VM-102 | Checks the ID of the video track within its container format. This is the 'PID' for MPEG-2 Transport Streams, the 'stream_id' for MPEG-2 Program Streams and the 'Track ID' for MOV and MXF files. |
Video Bit Rate | VM-103 | Check that the bit rate of the video track is within the given range, expressed in Mbit/s. |
Video Bit Rate Mode | VM-104 | Checks whether the bit rate mode of the video is variable (VBR) or constant (CBR). |
Codec | VM-105 | Tests the format of the video elementary stream. |
Color Space Information | VM-106 | This tests that the video has certain color space properties (e.g. color primaries, transfer characteristics and matrix coefficients). If a property is not found in the video, a Warning will be generated |
Frame Rate | VM-107 | Frame rate in video frames per second. "NTSC" denotes a drop frame rate, e.g. "30fps (NTSC)" corresponds to 29.97fps. |
Drop Frame | VM-108 | Specify whether the file must have drop/non-drop frame timecode. |
Frame Size | VM-109 | Choose from a selection of standard frame sizes, or specify a Custom frame size (e.g. 2000x1000). |
Frame Aspect Ratio | VM-111 | Choose from a selection of standard frame aspect ratios, or specify a custom value as an integer or floating point value (e.g. 3 or 1.4). |
Pixel Aspect Ratio | VM-112 | The aspect ratio of each luminance sample in the coded stream, either as coded directly or implied by the display aspect ratio and frame size. |
Pixel To Frame Aspect Ratio Comparison | VM-113 | This test checks for possible anamorphic video in a 4:3 frame. This will most easily be determined by showing rectangular pixels in a 4:3 frame, indicating that the pixels should be stretched during playback to achieve the standard square aspect ratio. |
Chroma Subsampling Format | VM-114 | Checks that the chroma subsampling format matches the user specified value. Only applicable for YUV-based video. |
Clean Aperture | VM-115 | Checks that the Clean Aperture of the video is equal to the Production Aperture. This implies that no cropping of the encoded picture is indicated by the container. This test also verifies that no Clean Aperture offset is indicated. Clean Aperture is a QuickTime concept, thus this test will only be performed on MOV containers. |
GOP Length | VM-116 | Check the distance between successive I-frames in the encoded video. For example, this distance will be 1 for I-frame only video and 12 for a long GOP sequence coded as 'IBBPBBPBBPBBI'. This test is suitable for GOP coded video, such as MPEG-2 and H.264. |
Advanced GOP Length | VM-117 | A more thorough GOP test for MPEG-2 and H.264 that can test for a range of GOP lengths, test for open and closed GOPs (MPEG-2 only), and allow special handling of first and last GOPs. The "First GOP" and "Last 2 GOPs" sections, when ticked, enable specific values to be given for the first and last two GOPs. The "Other GOPs" section will apply to any other GOP (possibly including the first and last GOPs if their specific sections are not ticked). The input boxes for I-frame distance and P-frame distance are comma-separated lists of distances or ranges of distances. For example, "12", "1-12", "1,12,15' and "1,12-15" are all valid inputs. The syntax ">5" and "<5" mean "greater than" and "less than" 5 frames, respectively. If the input is empty, then no check is performed (i.e., any distance is valid). It is possible to choose whether the test operates on the coded frame order or the displayed frame order. This distinction is only important when B-frames are present. The test can be configured to either show unique GOP length errors (default) or to show all of them. |
Video Reference Frames | VM-118 | Checks the maximum number of short-term and long-term reference frames, complementary reference field pairs, and non-paired reference fields that may be used by the decoding process for inter-prediction of any picture in the coded video sequence. This test is applicable for AVC and HEVC video codec. |
Dolby Vision Validation | VM-121 | Verifies compliance of input file with Dolby Vision metadata. |
TV/MPAA Rating | VM-123 | Checks the Type 0x05 Content Advisory Packet from the caption data packet in the video stream and compares the results to the value you set in the template. |
AFD Detection (Dynamic) | VM-124 | Tests the value of the Active Format Description (AFD) as sent in the User Data of an MPEG-2 video sequence. |
Video Buffer Size | VM-125 | When MPEG-2 is selected, this test checks the VBV buffer size reported in the stream. When AVC/H.264 is selected, this test checks the CPB buffer size reported in the stream. Minimum and Maximum values are specified in KiB (1024 bytes) and either value may be left blank if not required. The 'Video Codec' test must be enabled and set to 'MPEG-2' or 'AVC/H.264' before this test may be used. |
MOOV Atom | VM-127 | This check is to identify that there is only one MOOV atom in an mov/mp4 file. |
Single Sample Description | VM-128 | This test looks for the presence of multiple Sample Descriptions in the MOV/MP4 track metadata, which is often an indicator that such incompatible splicing has taken place. |
Video Essence Duration | VM-130 | Test if the essence is shorter/longer than specified value/range. |
Is PAL or NTSC | VM-131 | This checks if PAL/NTSC video is present. NTSC Broadcast Format: NTSC Standard: 525 total lines, 480 displayed lines. 29.97 frames/second (59.97 fields/sec). Interlaced video only. PAL Broadcast Format: PAL Standard: 625 total lines, 576 displayed lines. 25 frames/second (50 fields/sec). Interlaced video only. |
Video Quality
Audio Metadata
Audio Quality
Check | Identifier | Description |
---|---|---|
Peak Level | AQ-101 | Measures the Peak audio level throughout the program material, and will alert if it is in violation of the user specified value. The user can choose whether to measure as dBFS or dBTP. |
Phase Coherence | AQ-102 | Measures the phase coherence between channel pairs. Phase is measured on a scale of -1 to 1, where -1 means "completely out of phase" and 1 means "completely in phase/mono". |
Dual Mono | AQ-103 | Compares two audio streams and will alert if dual mono sections are detected between them. Max Allowed Duration units can be samples, milliseconds, seconds or percentage, where a dual mono section lasting less than this time window will be ignored. |
Clicks and Pops | AQ-104 | Detects transients or sudden changes in amplitude, such as those caused by noise on a digital or analog signal. The user can choose between low, medium or high sensitivity; high sensitivity is more likely to generate false positive results, but may also detect smaller transients which are deemed erroneous. |
Clipping | AQ-105 | Detects audio clipping by testing for successive samples of equal value. Quiet samples (those below a fixed small value) are supressed and do not count towards the clipping test. |
Integrated Loudness (inc Dialog Gating) | AQ-106 | Integrated Loudness is measured over the duration of the file. In calculating the loudness, the arrangement of channels is assumed as found in the Audio Layout settings. Dialog gating can be applied to ITU 1770-1, which will measure loudness only when dialog is present. ITU 1770-2, 1770-3, and 1770-4 options do not currently support dialog gating. |
Short-term Loudness | AQ-107 | Short-term Loudness is measured over a sliding rectangular time window. The measurement is not gated. The default window length of 3 seconds corresponds to EBU-Tech 3341 short-term mode. The Max Violations setting will report only the worst violation, in accordance with EBU-Tech 3341/EBU r128. The All Violations setting will report all violations. |
Momentary Loudness | AQ-108 | Momentary Loudness is measured over a 400ms sliding rectangular time window as per EBU-Tech 3341 Momentary mode. The measurement is not gated. The Max Violations setting will report only the worst violation, in accordance with EBU-Tech 3341/EBU r128. The All Violations setting will report all violations. |
Loudness Range (LUFS) | AQ-109 | Loudness Range is a measurement of the variation in loudness over the duration of a file. The algorithm is specified in EBU-Tech 3342 and produces an output Loudness Range (LRA) in terms of Loudness Units (LU). |
Minimum Level | AQ-110 | Measures the audio RMS level per channel using a sliding window of the user specified length. If the RMS level for a given channel drops below this level for a contiguous period equal to or longer than the window length, an alert will be raised. Due to the nature of the windowing function, if the period is longer than the window length, only the minimum measurement during the period will be given. |
Silence | AQ-111 | Detects both intentional and unintentional Silence. The threshold indicates the threshold below which an audio track is considered silent. If Digital Silence is selected, instead of using the threshold, the track is checked for the presence of absence of audio samples. |
PPM Level | AQ-112 | The peak level according to the "BBC Peak Program Meter" (IEC 60268-10 Type IIa) standard. The meter can operate in MS (sum/difference) mode (modes M3 and M6), or AB mode (individual channels). Note that in MS mode, only the sum is measured.
|
Channel Position | AQ-113 | Checks whether 5.1 channels are in the correct place by using known frequencies to analyze the baseband of the center and LFE channel and validating against what should be present. |
Test Tone | AQ-114 | Checks for the presence of a sine wave tone (a "test tone"), on each channel. Level is in dBFS peak-to-peak. If levels are supplied in RMS, approximately 3dB should be added; for example a -9dBFS RMS signal will measure -6dBFS peak-to-peak. |
EAS Tone | AQ-115 | Checks for the presence of an EAS (Emergency Alert System) tone. |
Audio Hiss Detection | AQ-117 | The Verification Unit applies a low pass filter to the frequency transform of the audio track and determines if tape hiss noise is present. By default, the verification unit is checking for hiss noise across the entire time domain above 15,000 Hz. |
Audio Hum Detection | AQ-118 | The Verification Unit applies a high pass filter to the frequency domain of the audio waveform to determine if 50 Hz or 60 Hz hum (mono tone frequency) is present (+/- 1 Hz) anywhere within the clip. |
Audio Description Track Detection | AQ-120 | Checks for an audio description channel on a given mix. User should specify the expected audio description and control channels. In advanced settings, the user can adjust the frequency and amplitude of the control channel as well as their tolerances. The test reports the audio description / control pair (if any) and alerts when it is not found where expected. |
Channel Mapping | AQ-121 | Checks the channel mapping of the given mix against an expected channel mapping. For reference, see the List Of Channel Labels. |
Comparative Loudness | AQ-123 | Detect mismatch in program loudness across multiple audio tracks. Loudness tolerance, mode standard and dialog gating parameters are available |
File Quality
Check | Identifier | Description |
---|---|---|
Media Demux Decode | FQ-101 | Checks and reports errors when demuxing or decoding the media. |
Distribution and Broadcast
Tables
MPEG-2 streams, section 8.5 (Table 8-13)
Level | Profile | ||||
---|---|---|---|---|---|
Simple | Main | SNR | Spatial | High | |
High | 80 | 100 all layers 80 mid+base layer 25 base layer | |||
High-1440 | 60 | 60 all layers 40 mid+base layer 15 base layer | 80 all layers 60 mid+base layer 20 base layer | ||
Main | 15 | 15 | 15 both layers 10 base layer | 20 all layers 15 mid+base layer 4 base layer | |
Low | 4 | 4 both layers 3 base layer |
MPEG-2 streams, section 8.5 (Table 8-14)
Level | Layer | Profile | ||||
---|---|---|---|---|---|---|
Simple | Main | SNR | Spatial | High | ||
High | Enh.2 Enh.1 Base | 9,781,248 | 12,222,464 9,781,248 3,047,424 | |||
High-1440 | Enh.2 Enh.1 Base | 7,340,032 | 7,340,032 4,882,432 1,835,008 | 9,781,248 7,340,032 2,441,216 |
List Of Channel Labels
Channel Label | Short Code |
---|---|
Unknown | U |
Left | L |
Right | R |
Center | C |
Low Frequency Effects | LFE |
Left Surround | LS |
Right Surround | RS |
Left Center | LC |
Right Center | RC |
Center Surround | CS |
Left Side | LSD |
Right Side | RSD |
Top Center | TCS |
Top Front Left | TFL |
Top Front Center | TFC |
Top Front Right | TFR |
Top Back Left | TBL |
Top Back Center | TBC |
Top Back Right | TBR |
Top Side Left | TSL |
Top Side Right | TSR |
Left Wide | LW |
Right Wide | RW |
Low Frequency Effects 2 | LFE2 |
Left Rear Surround | LRS |
Right Rear Surround | RRS |
Left Total | LT |
Right Total | RT |
Mono | M |
Updated 12 days ago