Elecard AVC Video Encoder

Elecard AVC Video Encoder is a GStreamer plugin for encoding into H.264/AVC (MPEG-4 Part 10, ISO/IEC 14496-10) streams.

Features

Elecard AVC Video Encoder has the following features:

• Supports adaptive quantization;

• Supports CAVLC and CABAC entropy encoding algorithms;

• Enables precise GOP structure adjustment;

• Supports various H.264 levels and profiles.

Parameter Description

Below is the table describing Elecard AVC Video Decoder parameters and their values:

Parameter Name	Description	Value Type	Available Values [range]	Default	Flags
afd-code	Specifies the Active Format Descriptor (AFD) used to describe the image format, in particular—to manage the way the video will be displayed on screens with various aspect ratios, including the stretching and cropping modes or black lines. AFD is used to improve the compatibility of video with various devices.	Enum	0 — Auto 2 — Box 16x9 Top 3 — Box 14x9 Top 4 — Box 16x9 Centre 8 — Full Frame 9 — 4x3 Centre 10 — 16x9 Centre 11 — 14x9 Centre 13 — 4x3 SNP 14x9 Centre 14 — 16x9 SNP 14x9 Centre 15 — 16x9 SNP 4x3 Centre	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
aq-mode	Specifies the Adaptive Quantization (AQ) mode. The following modes are available: None — AQ is not used; Complexity — complexity-based AQ; Luminance — AQ based on complexity and luminance masking; ROI — encoding mode where the frame ROI (Region of Interest) is encoded with a quantization parameter changed by a certain amount (QP_OFFSET); Inter-frame — AQ based on inter-frame dependencies, available only with lookahead; Variance — variance-based AQ.	Enum	0 — None 1 — Complexity 2 — Luminance 3 — ROI 4 — Inter-Frame 5 — Variance	5	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
aq-strength	Specifies the adaptive quantization strength by indicating the difference between the values of quantization parameters and the base level.	Unsigned Integer	[1 – 10]	4	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
ar-auto	Enables or disables the use of the auto aspect ratio for the stream.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
ar-mode	Specifies the aspect ratio mode. Available modes: PAR — picture aspect ratio; SAR — sample aspect ratio.	Enum	0 — PAR 1 — SAR	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
aspect-info	Enables or disables the writing of aspect info in the bitstream.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
b-frames-mode	Specifies the B-frame encoding mode. Available modes: All disposable — B-frames do not contain information needed for decoding other frames; All reference — B-frames contain information needed for decoding other frames. This mode provides higher quality of encoded data; Hierarchical — enables the encoder to use the hierarchical structure of B-frames when encoding. This mode increases the quality of encoded data. The B-frames number must be set to 3.	Enum	0 — All disposable 1 — All reference 2 — Hierarchical	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
bitrate-avg	Specifies the average bit rate in bits per second.	Unsigned Integer	[1024 – 288000000]	1500000	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
bitrate-max	Specifies the hypothetical stream scheduler rate in bits per second.	Unsigned Integer	[1024 – 288000000]	3000000	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
bitrate-mode	Specifies the rate control mode. Available modes: cqp — mode with fixed quantization parameters for all frames; vbr — mode with variable bit rate. The limitation on the maximum bit rate is taken into account; cbr — mode with constant bit rate. Accounts for the HRD model limitations that prevent the encoder buffer from overflowing and ensure the specified bit rate is maintained; abr — mode with average bit rate maintained throughout the entire video, but the limitation on the maximum bit rate is not taken into account; intra — mode with constant fixed encoded frame size, intended for use with AVC Intra profile.	Enum	0 — cqp 1 — vbr 2 — cbr 3 — abr 4 — intra	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
bitrate-pass	Specifies the multipass encoding mode: Single — single-pass encoding; Multi Analyze — statistics gathering and analysis mode; Multi Encode — encoding mode that uses stream data obtained during analysis; Multi Analyze Fast — robust mode for statistics gathering and analysis.	Enum	0 — Single 1 — Multi Analyze 2 — Multi Encode 3 — Multi Analyze Fast	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
bitrate-real	Displays the real average bit rate.	Double	[0 – 1E+10]	0	readable
bitrate-stat	Specifies the name of the file used for storing multipass statistics.	String		eavcenc_stat.log	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
chroma-format	Specifies the chroma format.	Enum	0 — Grayscale format (4:0:0) 1 — 4:2:0 chroma format 2 — 4:2:2 chroma format	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
colour-description	Enables or disables the writing of color primaries, transfer characteristics, and matrix coefficients in the bitstream.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
colour-primaries	Specifies the color primaries. Works only if colour-description parameter is enabled. Note that this parameter does not affect color space conversion, only the writing of metadata.	Enum	1 — BT.709 2 — Unspecified 4 — FCC 5 — BT.601 PAL 6 — BT.601 NTSC 7 — SMPTE 240 8 — Generic film 9 — BT.2020 10 — SMPTE 428 11 — SMPTE 431 12 — SMPTE 432 22 — EBU 3213	2 — Unspecified	readable, writable, changeable only in NULL or READY state
deblock-alpha	Specifies the intensity of filtering block artifacts on low quantization levels, which is used to decrease the visibility of sharp transitions between blocks in the video.	Integer	[−6 – 6]	−1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
deblock-beta	Specifies the threshold of filtering block artifacts at higher quantization levels, which is used to adjust the balance between preserving details and eliminating noises.	Integer	[−6 – 6]	−1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
deblock-control	Enables or disables the deblocking filter control.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
deblock-mode	Specifies the operation mode of the in-loop deblock filter: Deblock_Picture — mode for the deblock filter to be applied to an entire picture; Deblock_Disable — mode that switches deblock filter off, which can preserve individual details but increases the visibility of artifacts; Deblock_Slices — mode for the deblock filter to be applied separately to each slice, which is useful for increasing the speed of multislice encoding.	Enum	0 — Deblock_Picture 1 — Deblock_Disable 2 — Deblock_Slices	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
encoded-frames	Displays the number of encoded frames.	Unsigned Integer	[0 – 2147483647]	0	readable
entropy-mode	Specifies the entropy encoding mode. Available modes: CAVLC — encoding with the CAVLC algorithm that is less complex and offers higher processing speed. CABAC — encoding with the CABAC algorithm that provides better compression but requires larger CPU capacity.	Enum	0 — CAVLC 1 — CABAC	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
explicit-mv	Enables or disables explicit motion vectors for P- and B-slices. Explicit vectors may be useful in certain cases (e.g., for simple codecs or situations where motion precision is important). However, they are less useful in more common scenarios.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
field-order	Specifies picture encoding mode: Top Field First (TFF) — encoding mode for the top field lines to be processed first; Bottom Field First (BFF) — encoding mode for the bottom field lines to be processed first; Auto — mode for the order of processing fields to be determined automatically based on info from input video.	Enum	0 — TFF 1 — BFF 2 — Auto	2	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
fix-output-frame-rate	Enables or disables the use of fixed frame rate at output. When enabled, the output video will have a constant frame rate regardless of real-time values on input frames.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
fix-source-frame-rate	Enables or disables the overriding of input frame rate. Works together with the source-frame-rate parameter.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
force-idr	Specifies the PTS value to insert forced IDR frame.	Integer64	[-1 – 9223372036854775807]	-1	readable, writable
force-pic-struct-present-flag	Enables or disables the writing of the pic_struct_present flag to the bitstream.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
fps	Displays the average number of encoded frames per second.	Double	[0 – 100000]	0	readable
full-range-colors	Specifies whether the full range of levels is used to display the video. The full range (0–255) can be found in PC screens and devices supporting the extended range; the limited range (16–235 for luma and 16–240 for chroma components) is used in the majority of television and broadcasting standards. Note that the encoder does not modify data and only sets the flag corresponding to the color range in use.	Enum	0 — TV 1 — PC	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
gop-adaptive	Enables or disables the adaptive placing of B- and P-slices. When enabled, the encoder automatically adjusts the number of B- and P-slices depending on the scene complexity, which increases video quality and compresses data more efficiently.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
gop-infinite	Enables or disables encoding with an infinite GOP (Group of Pictures). If enabled, the stream is encoded starting with one IDR frame and subsequent P-frames without explicit limitations on the GOP length.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
gop-intra-refresh	Enables or disables the intra-frame refresh. When enabled, the encoder refreshes a part of the picture in each frame, encoding it with intra-blocks, which increases resistance to data losses during transmission. It is recommended to use this in the infinite GOP encoding mode.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
gop-max-bcount	Specifies the maximum number of subsequent B-frames in a GOP. This affects the GOP structure and the balance between the quality of the video and compression efficiency. It is recommended to use 3 B-frames only in combination with the hierarchical GOP structure to avoid the decrease in quality in case of more complex scenes.	Unsigned Integer	[0 – 3]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
gop-max-length	Specifies the maximum GOP length in frames, which affects the video stream structure and the balance between the quality of compression and the decoding complexity.	Unsigned Integer	[1 – 500]	250	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
gop-min-length	Specifies the minimum GOP length in frames, which affects the video stream structure and the balance between compression quality and decoding complexity.	Unsigned Integer	[1 – 500]	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
gop-reordering	Enables or disables GOP reordering.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
gop-time-length	Specifies the GOP length in milliseconds.	Integer	[-1 – 2147483647]	-1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
idr-frequency	Specifies the frequency of IDR frames’ appearance in the video stream. If the parameter is set to 1, each I-frame will be an IDR frame; if the value is 2, each second I-frame will be an IDR frame.	Unsigned Integer	[0 – 1000]	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
initial-delay	Specifies the initial occupancy of the HRD (Hypothetical Reference Decoder) buffer in 90-kilohertz ticks. This determines how much data will be loaded to the buffer before the decoding process starts.	Unsigned Integer	[1024 – 288000000]	36000	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
latency-avg 1	Displays the average encoding latency in milliseconds over a 5-second window.	Double	[0 – 1e+10]	0	readable
latency-max	Displays the maximum encoding latency in milliseconds over a 5-second window.	Integer	[0 – 2147483647]	0	readable
latency-min	Displays the minimum encoding latency in milliseconds over a 5-second window.	Integer	[0 – 2147483647]	0	readable
level	Specifies the H.264 codec level by setting limitations on the maximum values of bit rate, resolution, and other stream properties.	Enum	10 — Level 1.0 11 — Level 1.1 12 — Level 1.2 13 — Level 1.3 20 — Level 2.0 21 — Level 2.1 22 — Level 2.2 30 — Level 3.0 31 — Level 3.1 32 — Level 3.2 40 — Level 4.0 41 — Level 4.1 42 — Level 4.2 50 — Level 5.0 51 — Level 5.1 52 — Level 5.2 60 — Level 6.0 61 — Level 6.1 62 — Level 6.2 100 — Auto	100	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
license-state	Displays the component license state.	String		evaluation expired	readable
log2-max-frame-num	Specifies the log2 of the maximum frame number.	Integer	[4 – 16]	8	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
log2-max-pic-order-cnt-lsb	Specifies the log2 of the maximum picture count.	Integer	[4 – 16]	8	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
lookahead	Specifies the size of the lookahead buffer in frames. This buffer is used to analyze and predict subsequent frames, which enables the encoder to take more measured decisions when encoding and improve the quality of compression.	Unsigned Integer	[0 – 500]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
low-latency	Enables or disables the low-latency mode. If enabled, the encoder optimizes the encoding process to minimize latency, which is especially important for real-time cases such as videoconferencing or video streaming.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
matrix-coefficients	Specifies the matrix coefficients. Works only if colour-description parameter is enabled. Note that this parameter does not affect color space conversion, only the writing of metadata.	Enum	0 — Identity 1 — BT.709 2 — Unspecified 4 — FCC 5 — BT.601 PAL 6 — BT.601 NTSC 7 — SMPTE 240 8 — YCgCo 9 — BT.2020 NTSC 10 — BT.2020 C 11 — SMPTE 2085 12 — Chromaticity NC 13 — Chromaticity C 14 — BT.2100	2 — Unspecified	readable, writable, changeable only in NULL or READY state
mc-field-search	Enables/disables additional steps in the block search algorithm during encoding by field. When the second field refers to the first field, all part of the same frame, during inter-frame prediction, the best solution for preserving encoding quality would be to add vertical subpixel search that stays within the 0.5-pixel frame. Enabling this will require larger CPU capacity.	Boolean	true, false	false	readable, writable, changeable only in NULL or READY state
mc-subpel-refinement	Specifies the accuracy of motion prediction: QP — motion prediction with quarter-pixel accuracy, which is more precise and improves video quality, but requires larger CPU capacity; HP — motion prediction with half-pixel accuracy, which is less precise but offers better performance. It’s also not as demanding due to decreased CPU usage.	Enum	0 — QP 1 — HP	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
me-search-range	Specifies the maximum length of the motion vector in full pixels. This parameter determines the range that the encoder will rely on while searching for similar in-frame blocks when predicting motion. Increasing the range can make prediction more accurate, especially in complex scenes where objects can move over long distances. However, this will also require larger CPU capacity.	Unsigned Integer	[0 – 511]	255	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
me-unrestricted-mv	Enables or disables the use of motion vectors outside the frame. If enabled, the encoder can analyze motion vectors that go beyond the current frame, which increases motion precision accuracy, especially when objects go beyond the frame or appear on its borders. If disabled, only those vectors that do not extend beyond the frame are analyzed, which requires less CPU capacity but also decreases prediction accuracy.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
min-block-size	Specifies the inter-frame prediction size (16×16 pixels or less). Available sizes: 16×16 pixels — motion compensation is done on larger blocks, which requires smaller CPU capacity but decreases prediction accuracy, especially for small objects or complex motions; 8×8 pixels — ensures more accurate motion compensation due to smaller blocks being analyzed; this increases the quality of prediction in scenes with small moving objects but requires larger CPU capacity.	Enum	0 — 16х16 1 — 8×8 in P-slices (16×16 in B-frames only) 2 — 8×8 in P- and B-slices	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
mv-x-bslice	Specifies the maximum horizontal length of motion vectors in B-frames. This parameter helps control the accuracy and efficiency of motion prediction in B-frames to manage the compression quality and the use of hardware.	Unsigned Integer	[0 – 511]	255	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
mv-x-pslice	Specifies the maximum horizontal length of motion vectors in P-frames. This parameter helps to control the accuracy and efficiency of motion prediction in P-frames to manage the compression quality and the use of hardware.	Unsigned Integer	[0 – 511]	255	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
mv-y-bslice	Specifies the maximum vertical length of motion vectors in B-frames. This parameter helps to control the accuracy and efficiency of motion prediction in B-frames to manage the compression quality and the use of hardware.	Unsigned Integer	[0 – 511]	255	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
mv-y-pslice	Specifies the maximum vertical length of motion vectors in P-frames. This parameter helps to control the accuracy and efficiency of motion prediction in P-frames to manage the compression quality and the use of hardware.	Unsigned Integer	[0 – 511]	255	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
name	Specifies the component name.	String		eavcenc0	readable, writable
num-ref-idx-l0-active	Specifies the maximum reference index for reference picture list 0 that shall be used to decode each slice of the picture; list 0 is used if num_ref_idx_active_override_flag equals 0 per slice.	Integer	[0 – 16]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
num-ref-idx-l1-active	Specifies the maximum reference index for reference picture list 1 that shall be used to decode each slice of the picture; list 1 is used if num_ref_idx_active_override_flag equals 0 per slice.	Integer	[0 – 16]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
num-reference-frames	Specifies how many preceding frames can be used as references for encoding the current frame during motion prediction. Increasing the number can improve the accuracy of prediction, which is especially useful for complex scenes with fast motion. However, this will also require more CPU power and RAM.	Unsigned Integer	[0 – 16]	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
num-threads	Specifies the number of threads the encoder will create to parallelize the process of encoding. If the value is set to 0, the encoder determines the number of threads automatically.	Unsigned Integer	[0 – 16]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
output-frame-rate	When fix-output-frame-rate is enabled, timestamp values derived from output-frame-rate value will be used for output timestamps. Note that no frame rate conversion is performed.	Double	[1 – 100]	25	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
par-height	Specifies the vertical size of a pixel based on its horizontal size if non-standard pixel aspect ratio is used. In most cases, the pixel aspect ratio is 1:1, but in some formats such as SD, pixels can be rectangular. In this case, the PAR setting becomes crucial for correct image display.	Integer	[1 – 65535]	3	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
par-width	Specifies the horizontal size of a pixel based on its vertical size if non-standard pixel aspect ratio is used. In most cases, the pixel aspect ratio is 1:1, but in some formats such as SD, pixels can be rectangular. In this case, the PAR setting becomes crucial for correct image display.	Integer	[1 – 65535]	4	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
parent	Specifies the parent of the object.	String	Object of type GstObject		readable, writable
performance	Specifies pre-set parameters that can be selected to ensure a certain balance between the speed and quality of video encoding. Available modes: Custom — user mode that allows you to set the parameters manually and achieve the desired balance between speed and quality; Highest Quality — mode that offers the highest encoding quality but at the lowest speed; High Quality — mode that offers high encoding quality at a speed greater than in the highest quality mode; Optimal — mode that provides an optimal balance between speed and quality, which is suitable for the majority of scenarios; Fast Speed — mode that ensures fast encoding with average quality; Fastest Speed — fastest encoding mode.	Enum	0 — Custom 1 — Highest Quality 2 — High Quality 3 — Optimal 4 — Fast Speed 5 — Fastest Speed	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
pic-init-quant	Specifies the initial value of SliceQPY for each slice.	Unsigned Integer	[0 – 51]	26	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
pic-timing-utc	Enables or disables the use of UTC (Coordinated Universal Time) to synchronize picture timing. If enabled, the timestamps of frames in the video stream will use UTC, which can be useful to synchronize video with other streams or events in real time.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
picture-mode	Specifies the image encoding mode. Available modes: Frame mode — encoding is done in the frame format (progressive scan); Field mode — encoding is done in the field format (interlaced scan); MBAFF mode — an adaptive encoding mode (Macroblock Adaptive Frame/Field), where a decision to encode in frame or field format is taken for each macroblock separately; PAFF — an adaptive encoding mode (Picture Adaptive Frame Field), where the decision to encode in frame or field format is taken based on the entire frame; PAFF (MBAFF) — a combined adaptive mode, where the decision to code at the full frame level (PAFF) is taken first. Then, if the frame is identified as progressive, a more precise adaptation at the macroblock level (MBAFF) is used for it.	Enum	0 — Frame 1 — Field 2 — MBAFF 3 — PAFF Field 4 — PAFF MBAFF	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
poc-type	Specifies POC (Picture Order Count) in the video stream. Type 0 — a direct POC calculation where the slice number always increases by one in the order the slices are decoded; Type 2 — the display order is equal to the decoding order and there is only one non-reference frame between two reference frames.	Enum	0 — Type 0 2 — Type 2	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
pps-mode	Specifies how often a PPS (Picture Parameter Set) is written in the encoded stream. The frequency of PPS writing can be set based on stream compatibility and optimization requirements. Available modes: Each IDR — parameter set is written for each IDR frame; Each I-frame — parameter set is written for each I-frame; Each Picture — parameter set is written for each frame; Once — parameter set is written only once at the beginning of the encoding process; EverySecond — parameter set is written every second.	Enum	0 — Each IDR 1 — Each I-frame 2 — Each Picture 3 — Once 4 — EverySecond	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
preset	Enables selection of a preset of settings optimized for the most common media formats and hardware platforms. The use of presets simplifies the configuration of the encoding process and provides a balance between quality, speed, and compatibility for certain devices and formats.	Enum	0 — Custom 1 — Baseline 2 — Main 3 — High 4 — Apple iPOD 5 — Sony PSP 6 — DVD 7 — HD DVD 8 — Blu-Ray 9 — Blu-Ray HD 10 — HDV1 720p 11 — HDV2 1080i 12 — AVCHD 13 — Offline	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
profile	Specifies a H.264 profile that determines a set of functions and limitations for video stream decoding. Available profiles: Baseline — a profile with basic functions for applications with limited resources such as videoconferencing; Constraining Baseline — a modification of the Baseline profile with additional limitations aimed at increasing compatibility and tolerance to errors in a low-resource or real-time environment; Main — a profile with improved features, such as B-frames, suitable for broadcasting and video streaming; High — a profile that offers extended encoding capabilities. It is one of the most high-quality profiles in the H.264 specification; High422 — a profile for video with 4:2:2 chroma subsampling format used in professional production.	Enum	66 — Baseline 67 — ConstrBaseline 77 — Main 100 — High 122 — High422	66	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
psnr-avg	Displays the average PSNR over a 1-second window.	Double	[0 –100]	0	readable
pulldown	Specifies a mode for using pull-down to transform frames and fields from one frame rate format into another. Note that the encoder only sets metadata, specifically pic_struct in pic_timing SEI message, no frame rate conversion performed. Available options: None — pull-down is not used, which means frames and fields are transmitted without changes; 23i — 2–3 frames are used for interlaced scan; frames and fields come in the following order: t0, b0, t1, b1, t1, b2, t2, b3, t3, b3, etc; 32i — 3–2 frames are used for interlaced scan; frames and fields come in the following order: t0, b0, t0, b1, t1, b2, t2, b2, t3, etc; 23p — 2–3 frames are used for progressive scan; frames and fields come in the following order: f0, f0, f1, f1, f1, f2, f2, f3, f3, f3, etc; 32p — 3–2 frames are used for progressive scan; frames and fields come in the following order: f0, f0, f0, f1, f1, f2, f2, f2, f3, f3, etc; Auto — the mode of transformation between frames and fields is selected automatically; they come in the following order: t0, b0, t0, b1, t1, b2, t2, b2, t3, etc.	Enum	0 — None 1 — 23i 2 — 32i 3 — 23p 4 — 32p 5 — Auto	5	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
qp-avg	Displays the average quantization parameter over a 1-second window. This average accounts for and incorporates the QP delta values associated with different picture types (I, P, B).	Double	[0 – 51]	0	readable
quant-b	Specifies the quantization parameter for B-frames in CQP (Constant QP) video encoding mode.	Unsigned Integer	[0 – 51]	28	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
quant-i	Specifies the quantization parameter for I-frames in CQP (Constant QP) video encoding mode.	Unsigned Integer	[0 – 51]	23	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
quant-max	Specifies the maximum quantization parameter the encoder can use during video encoding. This specifies the top limit for compression to control the image quality and avoid excessive quality loss in case of high compression.	Unsigned Integer	[0 – 51]	51	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
quant-min	Specifies the minimum quantization parameter the encoder can use during video encoding. This specifies a lower limit for compression to control the detail level and avoid excessive file size increase when improving quality.	Unsigned Integer	[0 – 51]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
quant-offset-cb	Specifies the quantization offset for Cb chroma component, which affects the level of compression for color information in this component.	Integer	[-10 – 10]	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
quant-offset-cr	Specifies the quantization offset for Cr chroma component, which affects the level of compression for color information in this component.	Integer	[-10 – 10]	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
quant-p	Specifies the quantization value for P-frames in CQP (Constant QP) video encoding mode.	Unsigned Integer	[0 – 51]	25	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
quant-scale-mode	Specifies the quant scale mode.	Enum	0 — None 2 — SPS AVC Intra 50 3 — SPS AVC Intra 100	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
quant-trellis	Specifies the mode of Trellis optimization that uses the best quantization methods to minimize quality losses. Available options: PSNR — a PSNR method optimized for the PSNR (Peak Signal-to-Noise Ratio) metric, which helps minimize quality loss; HVS — a method optimized for human perception (HVS stands for Human Visual System), which ensures better visual perception of an image, taking into account the intricacies of human vision.	Enum	0 — Off 1 — PSNR 2 — HVS	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
rc-last-ip-frames	Specifies the number of I/P-frames that will be encoded at the end of the video stream. To use this feature, you need to set the size of the lookahead buffer to no less than N+B frames	Unsigned Integer	[0 – 499]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
rc-roi-height	Specifies the height of ROI in the frame when the ROI mode for adaptive quantization (ROI AQ) is selected.	Unsigned Integer	[0 – 16384]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
rc-roi-quant-offset	Specifies the quantization offset for ROI in the frame when the ROI mode for adaptive quantization is used.	Integer	[-18 – 18]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
rc-roi-width	Specifies the width of ROI in the frame when the ROI mode for adaptive quantization is used.	Unsigned Integer	[0 – 16384]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
rc-roi-x	Specifies the x coordinate of ROI in the frame when the ROI mode for adaptive quantization is used.	Unsigned Integer	[0 – 16384]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
rc-roi-y	Specifies the y coordinate of ROI in the frame when the ROI mode for adaptive quantization is used.	Unsigned Integer	[0 – 16384]	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
rd-metric	Specifies the RD metric. It is an optimization method that balances between image quality (distortion) and the compressed file size (bit rate). The main purpose of RD optimization is to minimize the distortion with maximum file compression. Available modes: SAD — Sum of Absolute Differences metric that assesses inaccuracies between blocks based on absolute differences, offering max processing speed; SATD — Sum of Absolute Transformed Differences metric that uses transformations for a more accurate comparison of blocks. SATD is more precise but requires more powerful hardware and time; RDO — Rate-Distortion Optimization metric that minimizes quality loss and provides optimal data compression. This is the most precise and resource-intensive metric that requires more time for processing; RDO_INTRA — Partial Rate-Distortion Optimization metric, applicable to I-pictures only.	Enum	0 — SAD 1 — SATD 2 — RDO 3 — RDO_INTRA	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
real-fps	Displays the current number of encoded frames per second.	Double	[0 – 100000]	0	readable
reencode-cnt-b 2	Displays the number of re-encodings of B-frames since the start of streaming and encoding.	Integer	[0 – 2147483647]	0	readable
reencode-cnt-i	Displays the number of re-encodings of I-frames since the start of streaming and encoding.	Integer	[0 – 2147483647]	0	readable
reencode-cnt-p	Displays the number of re-encodings of P-frames since the start of streaming and encoding.	Integer	[0 – 2147483647]	0	readable
sar-height	Specifies the height of SAR (Sample Aspect Ratio). The parameter is used if the custom aspect ratio is set. It indicates the height-width ratio image ratio, which helps adjust an image with an atypical aspect ratio.	Integer	[1 – 65535]	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
sar-width	Specifies the width of SAR (Sample Aspect Ratio). The parameter is used if the custom aspect ratio is set. It indicates the height-width ratio image ratio, which helps adjust an image with an atypical aspect ratio.	Integer	[1 – 65535]	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
sei-mode	Specifies a SEI (Supplemental Enhancement Information) transmission mode. SEI is used to transmit additional information in the video stream. This information doesn’t influence the decoding processes but can be useful for other purposes such as metadata management. Available modes: Unrestricted — a mode for SEI to be inserted in any part of the stream without limitations; One per NALU — a mode for SEI to be inserted only once per each NALU (Network Abstraction Layer Unit).	Enum	0 — Unrestricted 1 — One per NALU	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
slices-count	Specifies the number of slices per frame. Increasing the number of slices can speed up the encoding process, but can decrease the quality due to additional use of compression mechanisms for each slice.	Unsigned Integer	[1 – 99]	1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
source-frame-rate	Specifies the frame rate if the fixed source (input) frame rate is enabled.	Double	[1 – 100]	25	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
speed-mode	Specifies the encoding speed mode. Available values: 0 — encoding speed is not controlled; 1 — Encoding speed is set to quarter of realtime; 2 — Encoding speed is set to half realtime; 3 — Encoding speed is set to realtime; 4 — Encoding speed is set to double realtime; 5 — Encoding speed is set to quadruple realtime; 6 — Encoding speed is set to the value specified in the speed-value parameter.	Enum	0 — Default 1 — Quarter RealTime 2 — Half RealTime 3 — 1x RealTime 4 — 2x RealTime 5 — 4x RealTime 6 — Specified	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
speed-value	Specifies the encoding speed value (frames/sec) if the speed-mode parameter is set to Specified.	Unsigned Integer	[0 – 999]	25	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
sps-mode	Specifies how often an SPS (Sequence Parameter Set) is recorded in the encoded stream. SPS contains important parameters for video stream decoding, such as picture size, frame number, and other specifics required for correct decoding. The frequency of SPS recording can be set based on the requirements to stream compatibility and optimization. Available options: Each IDR — an SPS is written for each IDR-frame; Each I-frame — an SPS is written for each I-frame; Each Picture — an SPS is written for each frame; Once — an SPS is written only once at the beginning of the encoding process; Every Second — an SPS is written every second.	Enum	0 — Each IDR 1 — Each I-frame 2 — Each Picture 3 — Once 4 — Every Second	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
transfer-characteristics	Specifies the transfer characteristics. Works only if colour-description parameter is enabled. Note that this parameter does not affect color space conversion, only the writing of metadata.	Enum	1 — BT.709 2 — Unspecified 4 — FCC 5 — BT.601 PAL 6 — BT.601 NTSC 7 — SMPTE 240 8 — Linear 9 — Logarithmic 100:1 10 — Logarithmic 100*Sqrt(10):1 11 — IEC 61966-2-4 12 — BT.1361 13 — IEC 61966-2-1 14 — BT.2020 (10 bit) 15 — BT.2020 (12 bit) 16 — SMPTE 2084 (PQ) 17 — SMPTE 428 18 — BT.2100 (HLG)	2 — Unspecified	readable, writable, changeable only in NULL or READY state
transform-mode	Specifies the block transformation mode, which is used during video encoding. The 8×8 and adaptive modes are available in High profile only. Available modes: Only 4x4 — only the transformation of 4x4 blocks is used; Adaptive — the size of a block for transformation is selected based on the image’s parameters; Only 8x8 — only the transformation of 8x8 blocks is used 3.	Enum	0 — Only 4x4 1 — Adaptive 2 — Only 8x8	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-i16x16-dc-only-in-islice	Enables/disables the intra 16x16 DC only mode in intra slices.	Boolean	true, false	true	readable, writable, construct
use-i16x16-dc-only-in-pslice	Enables/disables the intra 16x16 DC only mode in predicted slices.	Boolean	true, false	false	readable, writable, construct
use-i16x16-dc-only-in-bslice	Enables/disables the intra 16x16 DC only mode in bidirectional predicted slices.	Boolean	true, false	false	readable, writable, construct
use-i16x16-in-bslice	Enables or disables the intra 16x16 mode in bidirectional predicted slices.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-i16x16-in-islice	Enables or disables the intra 16x16 mode in intra slices.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-i16x16-in-pslice	Enables or disables the intra 16x16 mode in predicted slices.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-i4x4-in-bslice	Enables or disables the intra 4x4 mode in bidirectional predicted slices.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-i4x4-in-islice	Enables or disables the intra 4x4 mode in intra slices.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-i4x4-in-pslice	Enables or disables the intra 4x4 mode in predicted slices.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-i8x8-in-bslice	Enables or disables the intra 8x8 mode in bidirectional predicted slices.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-i8x8-in-islice	Enables or disables the intra 8x8 mode in intra slices.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-i8x8-in-pslice	Enables or disables the intra 8x8 mode in predicted slices.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
use-metric	Specifies what quality metric is calculated.	Enum	0 — No metric 1 — PSNR	0 — None	readable, writable, changeable only in NULL or READY state
use-scd	Enables or disables the SCD (Scene Change Detection) mechanism. This mechanism enables the encoder to automatically detect the instances of sharp changes in the picture, such as transitions between various scenes, and adapt the GOP structure accordingly. Enabling SCD helps increase encoding quality.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
vbv-size	Specifies the encoded picture buffer, VBV, size in bits. This buffer is used to manage the data stream during encoding to ensure the video bit rate fits in the set limitations and avoid buffer overflow.	Unsigned Integer	[1024 – 288000000]	1200000	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
video-format	Specifies the video format.	Enum	0 — Component 1 — PAL 2 — NTSC 3 — SECAM 4 — MAC 5 — Unspecified	5	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
vui-ar-idc	Specifies the Aspect Ratio IDC in the VUI (Video Usability Information) header of the video stream.	Enum	-1 — Auto 0 — Unspecified 1 — 1:1 2 — 12:11 3 — 10:11 4 — 16:11 5 — 40:33 6 — 24:11 7 — 20:11 8 — 32:11 9 — 80:33 10 — 18:11 11 — 15:11 12 — 64:33 13 — 160:99 255 — Extended	-1	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
wpred-in-bslice	Enables or disables weighted prediction (WP) for bidirectional predicted frames (B-slices) and specifies the functioning mode. WP enables you to take into account the changes in brightness and contrast between frames by applying weighted coefficients to pixels for a more accurate prediction. This can improve the quality of encoding in scenes where lighting changes or objects move. Available modes: Explicit — explicit prediction where weighted coefficients are transmitted in the frame header; Implicit — implicit prediction where weighted coefficients are calculated automatically based on motion data and other specifics.	Enum	0 — Disable 1 — Explicit 2 — Implicit	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
wpred-in-pslice	Enables the encoder to use explicit weighted prediction (WP) for P-slices. WP takes into account the changes in brightness and contrast between the current and preceding frames, leading to improved prediction accuracy and encoding quality.	Enum	0 — Disable 1 — Enable	0	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
write-afd	Enables or disables the writing of active format descriptor to the bitstream.	Boolean	true, false	false	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
write-au-delimiters	Enables or disables the writing of access unit delimiters.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
write-hrd-params	Enables or disables the writing of HRD parameters.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state
write-seq-end-code	Enables or disables the writing of the end of sequence code.	Boolean	true, false	true	readable, writable, changeable in NULL, READY, PAUSED or PLAYING state

1

Latency is the time period in milliseconds during which a frame gets into and gets out of the encoder’s engine. latency-avg, latency-max, and latency-min parameters can help pinpoint whether the encoder specifically—and not any other component—is the reason for the stream’s latency.

2

Re-encoding is an instance of the encoder deciding that an encoded frame is bad-quality and as a result encoding it again. It could be due to the faulty frame being too large or going against the HRD model, making it impossible to stick to the target bitrate. reencode-cnt-b, reencode-cnt-i, and reencode-cnt-p parameters can help pinpoint one of the reasons for latency to occur in the encoder.

3

The Only 8x8 and Adaptive modes are available in High profile only.