hi_venc_h264_avbr_param

Description

Defines the advanced AVBR parameters of an H.264 encoding channel.

Prototype

hi_venc_h264_avbr_param = {"chg_pos": chg_pos,
                           "max_i_proportion": max_i_proportion,
                           "min_i_proportion": min_i_proportion,
                           "max_reencode_times": max_reencode_times,
                           "qpmap_en": qpmap_en,
                           "min_still_percent": min_still_percent,
                           "max_still_qp": max_still_qp,
                           "min_still_psnr": min_still_psnr,
                           "max_qp": max_qp,
                           "min_qp": min_qp,
                           "max_i_qp": max_i_qp,
                           "min_i_qp": min_i_qp,
                           "min_qp_delta": min_qp_delta,
                           "motion_sensitivity": motion_sensitivity,
                           "save_bitrate_en": save_bitrate_en}

Members

max_bit_rate indicates the maximum bit rate in the motion scenario. max_bit_rate*chg_pos*min_still_percent indicates the minimum bit rate in the static scenario.

The target bit rate is adjusted between the maximum bit rate and the minimum bit rate based on the motion degree. max_qp and min_qp are used to control the image quality. The bit rate control takes the QP clamping as the highest priority, and bit rate control becomes invalid if the range of [min_qp, max_qp] is exceeded.

max_bit_rate is a member variable in hi_venc_chn_attr["rc_attr"] and is set during VENC channel creation.

Member	Description
chg_pos	Int, proportion of the bit rate when the QP value starts to be adjusted in AVBR mode to the maximum bit rate. Value range: [50, 100] Default value: 65
min_i_proportion	Int, reserved.
max_i_proportion	Int, maximum bit rate proportion of I- and P-frames. Value range: [1, 100] Default value: 100
max_reencode_times	Int, number of times that each frame is re-encoded. If set to 0, disables re-encoding. Value range: [0, 3] Default value: 2
qpmap_en	Int, reserved.
min_still_percent	Int, minimum percentage of the destination bit rate in a still scene. If it is set to 100, AVBR does not adaptively decrease the target bit rate in the still state. Value range: [5, 100] Default value: 25
max_still_qp	Int, maximum QP value of an I-frame in a still scene. Value range: [MinIQp, MaxIQp] Default value: 35
min_still_psnr	Int, reserved.
max_qp	Int, maximum QP value of P and B-frames. Value range: [0, 51] Default value: 51
min_qp	Int, minimum QP value of P- and B-frames. Value range: [0, max_qp] Default value: 24
max_i_qp	Int, maximum QP value of an I-frame. Value range: [0, 51] Default value: 51
min_i_qp	Int, minimum QP value of an I-frame. Value range: [0, max_i_qp] Default value: 24
min_qp_delta	Int, difference between the frame-level and CU-level minimum QP values. Min. QP of I-frames = min_qp_delta + min_i_qp Min. QP of P-/B-frames = min_qp_delta + min_qp Value range: [0, 4] Default value: 0
motion_sensitivity	Int, motion sensitivity. Value range: [0, 100] Default value: 100
save_bitrate_en	Int, reserved.

Parent topic: Video/Image Encoding