From ff1bde1d81d3f28c9079e8c274748253eb93b8d8 Mon Sep 17 00:00:00 2001 From: Yonit Halperin Date: Mon, 18 Feb 2013 09:25:43 -0500 Subject: mjpeg_encoder: keep the average observed fps similar to the defined fps The actual frames distribution does not necessarily fit the condition "at least one frame every (1000/rate_contorl->fps) milliseconds". For keeping the average frame rate close to the defined fps, we periodically measure the current average fps, and modify rate_control->adjusted_fps accordingly. Then, we use (1000/rate_control->adjusted_fps) as the interval between the frames. --- server/mjpeg_encoder.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 73 insertions(+), 2 deletions(-) (limited to 'server') diff --git a/server/mjpeg_encoder.c b/server/mjpeg_encoder.c index ac929248..41d234ec 100644 --- a/server/mjpeg_encoder.c +++ b/server/mjpeg_encoder.c @@ -51,6 +51,8 @@ static const int mjpeg_quality_samples[MJPEG_QUALITY_SAMPLE_NUM] = {20, 30, 40, #define MJPEG_CLIENT_POSITIVE_REPORT_TIMEOUT 2000 #define MJPEG_CLIENT_POSITIVE_REPORT_STRICT_TIMEOUT 3000 +#define MJPEG_ADJUST_FPS_TIMEOUT 500 + /* * avoid interrupting the playback when there are temporary * incidents of instability (with respect to server and client drops) @@ -105,6 +107,7 @@ typedef struct MJpegEncoderBitRateInfo { uint32_t num_enc_frames; uint64_t sum_enc_size; } MJpegEncoderBitRateInfo; + /* * Adjusting the stream jpeg quality and frame rate (fps): * When during_quality_eval=TRUE, we compress different frames with different @@ -125,6 +128,10 @@ typedef struct MJpegEncoderRateControl { uint64_t byte_rate; int quality_id; uint32_t fps; + double adjusted_fps; + uint64_t adjusted_fps_start_time; + uint64_t adjusted_fps_num_frames; + /* the encoded frame size which the quality and the fps evaluation was based upon */ uint64_t base_enc_size; @@ -132,6 +139,7 @@ typedef struct MJpegEncoderRateControl { uint64_t sum_recent_enc_size; uint32_t num_recent_enc_frames; + } MJpegEncoderRateControl; struct MJpegEncoder { @@ -355,6 +363,7 @@ static inline void mjpeg_encoder_reset_quality(MJpegEncoder *encoder, uint64_t frame_enc_size) { MJpegEncoderRateControl *rate_control = &encoder->rate_control; + double fps_ratio; rate_control->during_quality_eval = FALSE; @@ -362,7 +371,6 @@ static inline void mjpeg_encoder_reset_quality(MJpegEncoder *encoder, rate_control->last_enc_size = 0; } - if (rate_control->quality_eval_data.reason == MJPEG_QUALITY_EVAL_REASON_RATE_CHANGE) { memset(&rate_control->server_state, 0, sizeof(MJpegEncoderServerState)); } @@ -371,8 +379,17 @@ static inline void mjpeg_encoder_reset_quality(MJpegEncoder *encoder, rate_control->quality_eval_data.max_quality_id = MJPEG_QUALITY_SAMPLE_NUM - 1; rate_control->quality_eval_data.max_quality_fps = MJPEG_MAX_FPS; + if (rate_control->adjusted_fps) { + fps_ratio = rate_control->adjusted_fps / rate_control->fps; + } else { + fps_ratio = 1.5; + } rate_control->fps = MAX(MJPEG_MIN_FPS, fps); rate_control->fps = MIN(MJPEG_MAX_FPS, rate_control->fps); + rate_control->adjusted_fps = rate_control->fps*fps_ratio; + spice_debug("adjusted-fps-ratio=%.2f adjusted-fps=%.2f", fps_ratio, rate_control->adjusted_fps); + rate_control->adjusted_fps_start_time = 0; + rate_control->adjusted_fps_num_frames = 0; rate_control->base_enc_size = frame_enc_size; rate_control->sum_recent_enc_size = 0; @@ -640,6 +657,54 @@ end: } } +/* + * The actual frames distribution does not necessarily fit the condition "at least + * one frame every (1000/rate_contorl->fps) milliseconds". + * For keeping the average fps close to the defined fps, we periodically + * measure the current average fps, and modify rate_control->adjusted_fps accordingly. + * Then, we use (1000/rate_control->adjusted_fps) as the interval between frames. + */ +static void mjpeg_encoder_adjust_fps(MJpegEncoder *encoder, uint64_t now) +{ + MJpegEncoderRateControl *rate_control = &encoder->rate_control; + uint64_t adjusted_fps_time_passed; + + if (!encoder->rate_control_is_active) { + return; + } + adjusted_fps_time_passed = (now - rate_control->adjusted_fps_start_time) / 1000 / 1000; + + if (!rate_control->during_quality_eval && + adjusted_fps_time_passed > MJPEG_ADJUST_FPS_TIMEOUT && + adjusted_fps_time_passed > 1000 / rate_control->adjusted_fps) { + double avg_fps; + double fps_ratio; + + avg_fps = ((double)rate_control->adjusted_fps_num_frames*1000) / + adjusted_fps_time_passed; + spice_debug("#frames-adjust=%lu #adjust-time=%lu avg-fps=%.2f", + rate_control->adjusted_fps_num_frames, adjusted_fps_time_passed, avg_fps); + spice_debug("defined=%u old-adjusted=%.2f", rate_control->fps, rate_control->adjusted_fps); + fps_ratio = avg_fps / rate_control->fps; + if (avg_fps + 0.5 < rate_control->fps && + encoder->cbs.get_source_fps(encoder->cbs_opaque) > avg_fps) { + double new_adjusted_fps = avg_fps ? + (rate_control->adjusted_fps/fps_ratio) : + rate_control->adjusted_fps * 2; + + rate_control->adjusted_fps = MIN(rate_control->fps*2, new_adjusted_fps); + spice_debug("new-adjusted-fps=%.2f", rate_control->adjusted_fps); + } else if (rate_control->fps + 0.5 < avg_fps) { + double new_adjusted_fps = rate_control->adjusted_fps / fps_ratio; + + rate_control->adjusted_fps = MAX(rate_control->fps, new_adjusted_fps); + spice_debug("new-adjusted-fps=%.2f", rate_control->adjusted_fps); + } + rate_control->adjusted_fps_start_time = now; + rate_control->adjusted_fps_num_frames = 0; + } +} + int mjpeg_encoder_start_frame(MJpegEncoder *encoder, SpiceBitmapFmt format, int width, int height, uint8_t **dest, size_t *dest_len, @@ -655,9 +720,14 @@ int mjpeg_encoder_start_frame(MJpegEncoder *encoder, SpiceBitmapFmt format, clock_gettime(CLOCK_MONOTONIC, &time); now = ((uint64_t) time.tv_sec) * 1000000000 + time.tv_nsec; + + if (!rate_control->adjusted_fps_start_time) { + rate_control->adjusted_fps_start_time = now; + } + mjpeg_encoder_adjust_fps(encoder, now); interval = (now - rate_control->bit_rate_info.last_frame_time); - if (interval < (1000*1000*1000) / rate_control->fps) { + if (interval < (1000*1000*1000) / rate_control->adjusted_fps) { return MJPEG_ENCODER_FRAME_DROP; } @@ -782,6 +852,7 @@ size_t mjpeg_encoder_end_frame(MJpegEncoder *encoder) } rate_control->sum_recent_enc_size += rate_control->last_enc_size; rate_control->num_recent_enc_frames++; + rate_control->adjusted_fps_num_frames++; } rate_control->bit_rate_info.sum_enc_size += encoder->rate_control.last_enc_size; rate_control->bit_rate_info.num_enc_frames++; -- cgit