[Spice-devel] [spice] mjpeg: Pull more code in get_min_required_playback_delay()

[Francois Gouget]

This reduces code duplication and passing the MJpegEncoder object
makes it possible to modify the playback calculation without adding
more arguments.

Signed-off-by: Francois Gouget <fgouget at codeweavers.com>
---
 server/mjpeg-encoder.c | 31 +++++++++++++------------------
 1 file changed, 13 insertions(+), 18 deletions(-)

diff --git a/server/mjpeg-encoder.c b/server/mjpeg-encoder.c
index 1400519bb..15db38752 100644
--- a/server/mjpeg-encoder.c
+++ b/server/mjpeg-encoder.c
@@ -181,9 +181,8 @@ typedef struct MJpegEncoder {
 } MJpegEncoder;
 
 static void mjpeg_encoder_process_server_drops(MJpegEncoder *encoder);
-static uint32_t get_min_required_playback_delay(uint64_t frame_enc_size,
-                                                uint64_t byte_rate,
-                                                uint32_t latency);
+static uint32_t get_min_required_playback_delay(MJpegEncoder *encoder,
+                                                uint64_t frame_enc_size);
 
 static void mjpeg_video_buffer_free(VideoBuffer *video_buffer)
 {
@@ -534,10 +533,7 @@ complete_sample:
     spice_debug("MJpeg quality sample end %p: quality %d fps %d",
                 encoder, mjpeg_quality_samples[rate_control->quality_id], rate_control->fps);
     if (encoder->cbs.update_client_playback_delay) {
-        uint32_t latency = mjpeg_encoder_get_latency(encoder);
-        uint32_t min_delay = get_min_required_playback_delay(final_quality_enc_size,
-                                                             rate_control->byte_rate,
-                                                             latency);
+        uint32_t min_delay = get_min_required_playback_delay(encoder, final_quality_enc_size);
 
         encoder->cbs.update_client_playback_delay(encoder->cbs.opaque, min_delay);
     }
@@ -1166,20 +1162,20 @@ static void mjpeg_encoder_handle_positive_client_stream_report(MJpegEncoder *enc
  * the video playback jitter buffer should be at least (send_time*2 + net_latency) for
  * preventing underflow
  */
-static uint32_t get_min_required_playback_delay(uint64_t frame_enc_size,
-                                                uint64_t byte_rate,
-                                                uint32_t latency)
+static uint32_t get_min_required_playback_delay(MJpegEncoder *encoder,
+                                                uint64_t frame_enc_size)
 {
-    uint32_t one_frame_time;
-    uint32_t min_delay;
+    MJpegEncoderRateControl *rate_control = &encoder->rate_control;
+    uint32_t latency, one_frame_time, min_delay;
 
-    if (!frame_enc_size || !byte_rate) {
+    latency = mjpeg_encoder_get_latency(encoder);
+    if (!frame_enc_size || !rate_control->byte_rate) {
         return latency;
     }
-    one_frame_time = (frame_enc_size * MSEC_PER_SEC) / byte_rate;
 
-    min_delay = MIN(one_frame_time*2 + latency, MJPEG_MAX_CLIENT_PLAYBACK_DELAY);
-    return min_delay;
+    one_frame_time = (frame_enc_size * MSEC_PER_SEC) / rate_control->byte_rate;
+    min_delay = latency + 2 * one_frame_time;
+    return MIN(min_delay, MJPEG_MAX_CLIENT_PLAYBACK_DELAY);
 }
 
 #define MJPEG_PLAYBACK_LATENCY_DECREASE_FACTOR 0.5
@@ -1219,8 +1215,7 @@ static void mjpeg_encoder_client_stream_report(VideoEncoder *video_encoder,
                        rate_control->num_recent_enc_frames;
     }
     spice_debug("recent size avg %.2f (KB)", avg_enc_size / 1024.0);
-    min_playback_delay = get_min_required_playback_delay(avg_enc_size, rate_control->byte_rate,
-                                                         mjpeg_encoder_get_latency(encoder));
+    min_playback_delay = get_min_required_playback_delay(encoder, avg_enc_size);
     spice_debug("min-delay %u client-delay %d", min_playback_delay, end_frame_delay);
 
     if (min_playback_delay > end_frame_delay) {
-- 
2.20.1