hi_venc_vui_h264_time_info
Description
Defines the clock tick count information in the VUI of an H.264 encoding channel.
Prototype
typedef struct {
hi_u8 timing_info_present_flag;
hi_u8 fixed_frame_rate_flag;
hi_u32 num_units_in_tick;
hi_u32 time_scale;
} hi_venc_vui_h264_time_info;
Members
Member |
Description |
|---|---|
timing_info_present_flag |
Flag that indicates whether the clock tick count information in the VUI field takes effect. The options are 0 and 1. Other parameters in the table are valid only when this flag is set to 1. |
fixed_frame_rate_flag |
For details, see the H.264 protocol. The default value is 1. The options are 0 and 1. |
num_units_in_tick |
Number of time units elapsed when the clock tick counter is increased by 1. The value must be larger than 0. The default value is 1. |
time_scale |
Number of time units elapsed within one second. The value must be larger than 0. The default value is 60. |
Considerations
The clock tick count is used to mark video frame signals. In this H.264 encoder, the video display frame rate can be calculated according to the following formula: display_rate = time_scale/num_units_in_tick/2.
Since the display frame rate is only related to the ratio of time_scale to num_units_in_tick, you are advised to retain the value of num_units_in_tick to 1 during setting, and adjust the display frame rate through the time_scale parameter. At this time, the display_rate = time_scale/2.
The player determines the display frame rate, and can choose not to reference the TimeInfo information.