def update_batch_delay(batch, factors):
"""
Given a list of factors of the form:
[(description, factor, weight)]
we calculate a new batch delay.
We use a time-weighted average of previous delays as a starting value,
then combine it with the new factors.
"""
last_updated = batch.last_updated
current_delay = batch.delay
now = time.time()
avg = 0
tv, tw = 0.0, 0.0
decay = max(1, logp(current_delay / batch.min_delay) / 5.0)
max_delay = batch.max_delay
for delays in (batch.last_delays, batch.last_actual_delays):
if len(delays) > 0:
#get the weighted average
#older values matter less, we decay them according to how much we batch already
#(older values matter more when we batch a lot)
for when, delay in list(delays):
#newer matter more:
w = 1.0 / (1.0 + ((now - when) / decay)**2)
d = max(0, min(max_delay, delay))
tv += d * w
tw += w
if tw > 0:
avg = tv / tw
hist_w = tw
valid_factors = [x for x in factors if x is not None]
all_factors_weight = sum([w for _, _, w in valid_factors])
if all_factors_weight == 0:
log("update_batch_delay: no weights yet!")
return
for _, factor, weight in valid_factors:
target_delay = max(0, min(max_delay, current_delay * factor))
w = max(1, hist_w) * weight / all_factors_weight
tw += w
tv += target_delay * w
batch.delay = max(0, min(max_delay, tv / tw))
batch.last_updated = now
if DEBUG_DELAY > 0:
decimal_delays = [x for _, x in list(batch.last_delays)]
if len(decimal_delays) == 0:
decimal_delays.append(0)
rec = (
"update_batch_delay: wid=%s, last updated %.2f ms ago, decay=%.2fs, change factor=%.1f%%, delay min=%i, avg=%i, max=%i, cur=%.1f, w. average=%.1f, tot wgt=%.1f, hist_w=%.1f, new delay=%.1f",
batch.wid, 1000.0 * now - 1000.0 * last_updated,
decay, 100.0 * (batch.delay / current_delay - 1),
min(decimal_delays), sum(decimal_delays) / len(decimal_delays),
max(decimal_delays), current_delay, avg, tw, hist_w, batch.delay)
add_DEBUG_MESSAGE(*rec)
if DEBUG_DELAY > 1:
logfactors = [("{0:+}".format(int(100.0 * f - 100.0)).rjust(4) +
str(int(100 * w)).rjust(8) + " " + msg)
for (msg, f, w) in valid_factors]
add_DEBUG_MESSAGE("Factors (change - weight - description):\n " +
("\n ".join([str(x) for x in logfactors])))
def update_batch_delay(batch, factors):
"""
Given a list of factors of the form:
[(description, factor, weight)]
we calculate a new batch delay.
We use a time-weighted average of previous delays as a starting value,
then combine it with the new factors.
"""
last_updated = batch.last_updated
current_delay = batch.delay
now = time.time()
avg = 0
tv, tw = 0.0, 0.0
decay = max(1, logp(current_delay / batch.min_delay) / 5.0)
max_delay = batch.max_delay
for delays in (batch.last_delays, batch.last_actual_delays):
if len(delays) > 0:
# get the weighted average
# older values matter less, we decay them according to how much we batch already
# (older values matter more when we batch a lot)
for when, delay in list(delays):
# newer matter more:
w = 1.0 / (1.0 + ((now - when) / decay) ** 2)
d = max(0, min(max_delay, delay))
tv += d * w
tw += w
if tw > 0:
avg = tv / tw
hist_w = tw
valid_factors = [x for x in factors if x is not None]
all_factors_weight = sum([w for _, _, w in valid_factors])
if all_factors_weight == 0:
log("update_batch_delay: no weights yet!")
return
for _, factor, weight in valid_factors:
target_delay = max(0, min(max_delay, current_delay * factor))
w = max(1, hist_w) * weight / all_factors_weight
tw += w
tv += target_delay * w
batch.delay = max(0, min(max_delay, tv / tw))
batch.last_updated = now
if DEBUG_DELAY > 0:
decimal_delays = [x for _, x in list(batch.last_delays)]
if len(decimal_delays) == 0:
decimal_delays.append(0)
rec = (
"update_batch_delay: wid=%s, last updated %.2f ms ago, decay=%.2fs, change factor=%.1f%%, delay min=%i, avg=%i, max=%i, cur=%.1f, w. average=%.1f, tot wgt=%.1f, hist_w=%.1f, new delay=%.1f",
batch.wid,
1000.0 * now - 1000.0 * last_updated,
decay,
100.0 * (batch.delay / current_delay - 1),
min(decimal_delays),
sum(decimal_delays) / len(decimal_delays),
max(decimal_delays),
current_delay,
avg,
tw,
hist_w,
batch.delay,
)
add_DEBUG_MESSAGE(*rec)
if DEBUG_DELAY > 1:
logfactors = [
("{0:+}".format(int(100.0 * f - 100.0)).rjust(4) + str(int(100 * w)).rjust(8) + " " + msg)
for (msg, f, w) in valid_factors
]
add_DEBUG_MESSAGE(
"Factors (change - weight - description):\n " + ("\n ".join([str(x) for x in logfactors]))
)
def update_video_encoder(
wid,
window_dimensions,
batch,
global_statistics,
statistics,
video_encoder=None,
video_encoder_lock=None,
video_encoder_speed=None,
video_encoder_quality=None,
fixed_quality=-1,
min_quality=-1,
fixed_speed=-1,
min_speed=-1,
):
low_limit = get_low_limit(global_statistics.mmap_size > 0, window_dimensions)
# ***********************************************************
# encoding speed:
# 0 for highest compression/slower
# 100 for lowest compression/fast
# here we try to minimize damage-latency and client decoding speed
if fixed_speed >= 0:
new_speed = fixed_speed
if DEBUG_VIDEO:
add_DEBUG_MESSAGE("video encoder using fixed speed: %s", fixed_speed)
else:
# 20ms + 50ms per MPixel
min_damage_latency = 0.010 + 0.025 * low_limit / 1024.0 / 1024.0
target_damage_latency = min_damage_latency + batch.delay / 1000.0
dam_lat_abs = max(0, ((statistics.avg_damage_in_latency or 0) - min_damage_latency) * 10.0)
dam_lat_rel = max(0, ((statistics.avg_damage_in_latency or 0) / target_damage_latency) / 2.0)
target_decode_speed = 8 * 1000 * 1000 # 8 MPixels/s
dec_lat = 0.0
if statistics.avg_decode_speed:
dec_lat = target_decode_speed / (statistics.avg_decode_speed or target_decode_speed)
target = max(dam_lat_abs, dam_lat_rel, dec_lat, 0.0)
ms = min(100.0, max(min_speed, 0.0))
target_speed = ms + (100.0 - ms) * min(1.0, target)
# make a copy to work on
ves_copy = list(video_encoder_speed)
ves_copy.append((time.time(), target_speed))
new_speed = max(ms, time_weighted_average(ves_copy, min_offset=0.1, rpow=1.2))
if DEBUG_VIDEO:
msg = (
"video encoder speed factors: wid=%s, low_limit=%s, min speed=%s, min_damage_latency=%.3f, avg damage in latency=%.3f, target_damage_latency=%.3f, batch.delay=%.1f, dam_lat=%.3f / %.3f, dec_lat=%.3f, target=%i, new_speed=%i",
wid,
low_limit,
min_speed,
min_damage_latency,
statistics.avg_damage_in_latency,
target_damage_latency,
batch.delay,
dam_lat_abs,
dam_lat_rel,
dec_lat,
int(target_speed),
int(new_speed),
)
add_DEBUG_MESSAGE(*msg)
# ***********************************************************
# quality:
# 0 for lowest quality (low bandwidth usage)
# 100 for best quality (high bandwidth usage)
# here we try minimize client-latency, packet-backlog and batch.delay
if fixed_quality >= 0:
new_quality = fixed_quality
if DEBUG_VIDEO:
add_DEBUG_MESSAGE("video encoder using fixed quality: %s", fixed_quality)
else:
packets_backlog, _, _ = statistics.get_backlog()
packets_bl = 1.0 - logp(packets_backlog / low_limit)
batch_q = batch.min_delay / max(batch.min_delay, batch.delay)
target = min(packets_bl, batch_q)
latency_q = 0.0
if len(global_statistics.client_latency) > 0 and global_statistics.recent_client_latency > 0:
latency_q = 6.0 * statistics.target_latency / global_statistics.recent_client_latency
target = min(target, latency_q)
target = min(1.0, max(0.0, target))
mq = min(100.0, max(min_quality, 0.0))
target_quality = mq + (100.0 - mq) * min(1.0, target)
# make a copy to work on
veq_copy = list(video_encoder_quality)
veq_copy.append((time.time(), target_quality))
new_quality = max(mq, time_weighted_average(veq_copy, min_offset=0.1, rpow=1.1))
if DEBUG_VIDEO:
msg = (
"video encoder quality factors: wid=%s, min quality=%s, packets_bl=%.2f, batch_q=%.2f, latency_q=%.2f, target=%s, new_quality=%s",
wid,
min_quality,
packets_bl,
batch_q,
latency_q,
int(target_quality),
int(new_quality),
)
add_DEBUG_MESSAGE(*msg)
video_encoder_speed.append((time.time(), new_speed))
video_encoder_quality.append((time.time(), new_quality))
try:
video_encoder_lock.acquire()
if not video_encoder.is_closed():
video_encoder.set_encoding_speed(new_speed)
video_encoder.set_encoding_quality(new_quality)
finally:
video_encoder_lock.release()
def update_video_encoder(wid,
window_dimensions,
batch,
global_statistics,
statistics,
video_encoder=None,
video_encoder_lock=None,
video_encoder_speed=None,
video_encoder_quality=None,
fixed_quality=-1,
min_quality=-1,
fixed_speed=-1,
min_speed=-1):
low_limit = get_low_limit(global_statistics.mmap_size > 0,
window_dimensions)
#***********************************************************
# encoding speed:
# 0 for highest compression/slower
# 100 for lowest compression/fast
# here we try to minimize damage-latency and client decoding speed
if fixed_speed >= 0:
new_speed = fixed_speed
if DEBUG_VIDEO:
add_DEBUG_MESSAGE("video encoder using fixed speed: %s",
fixed_speed)
else:
#20ms + 50ms per MPixel
min_damage_latency = 0.010 + 0.025 * low_limit / 1024.0 / 1024.0
target_damage_latency = min_damage_latency + batch.delay / 1000.0
dam_lat_abs = max(
0, ((statistics.avg_damage_in_latency or 0) - min_damage_latency) *
10.0)
dam_lat_rel = max(
0,
((statistics.avg_damage_in_latency or 0) / target_damage_latency) /
2.0)
target_decode_speed = 8 * 1000 * 1000 #8 MPixels/s
dec_lat = 0.0
if statistics.avg_decode_speed:
dec_lat = target_decode_speed / (statistics.avg_decode_speed
or target_decode_speed)
target = max(dam_lat_abs, dam_lat_rel, dec_lat, 0.0)
ms = min(100.0, max(min_speed, 0.0))
target_speed = ms + (100.0 - ms) * min(1.0, target)
#make a copy to work on
ves_copy = list(video_encoder_speed)
ves_copy.append((time.time(), target_speed))
new_speed = max(
ms, time_weighted_average(ves_copy, min_offset=0.1, rpow=1.2))
if DEBUG_VIDEO:
msg = "video encoder speed factors: wid=%s, low_limit=%s, min speed=%s, min_damage_latency=%.3f, avg damage in latency=%.3f, target_damage_latency=%.3f, batch.delay=%.1f, dam_lat=%.3f / %.3f, dec_lat=%.3f, target=%i, new_speed=%i", \
wid, low_limit, min_speed, min_damage_latency, statistics.avg_damage_in_latency, target_damage_latency, batch.delay, dam_lat_abs, dam_lat_rel, dec_lat, int(target_speed), int(new_speed)
add_DEBUG_MESSAGE(*msg)
#***********************************************************
# quality:
# 0 for lowest quality (low bandwidth usage)
# 100 for best quality (high bandwidth usage)
# here we try minimize client-latency, packet-backlog and batch.delay
if fixed_quality >= 0:
new_quality = fixed_quality
if DEBUG_VIDEO:
add_DEBUG_MESSAGE("video encoder using fixed quality: %s",
fixed_quality)
else:
packets_backlog, _, _ = statistics.get_backlog()
packets_bl = 1.0 - logp(packets_backlog / low_limit)
batch_q = batch.min_delay / max(batch.min_delay, batch.delay)
target = min(packets_bl, batch_q)
latency_q = 0.0
if len(global_statistics.client_latency
) > 0 and global_statistics.recent_client_latency > 0:
latency_q = 6.0 * statistics.target_latency / global_statistics.recent_client_latency
target = min(target, latency_q)
target = min(1.0, max(0.0, target))
mq = min(100.0, max(min_quality, 0.0))
target_quality = mq + (100.0 - mq) * min(1.0, target)
#make a copy to work on
veq_copy = list(video_encoder_quality)
veq_copy.append((time.time(), target_quality))
new_quality = max(
mq, time_weighted_average(veq_copy, min_offset=0.1, rpow=1.1))
if DEBUG_VIDEO:
msg = "video encoder quality factors: wid=%s, min quality=%s, packets_bl=%.2f, batch_q=%.2f, latency_q=%.2f, target=%s, new_quality=%s", \
wid, min_quality, packets_bl, batch_q, latency_q, int(target_quality), int(new_quality)
add_DEBUG_MESSAGE(*msg)
video_encoder_speed.append((time.time(), new_speed))
video_encoder_quality.append((time.time(), new_quality))
try:
video_encoder_lock.acquire()
if not video_encoder.is_closed():
video_encoder.set_encoding_speed(new_speed)
video_encoder.set_encoding_quality(new_quality)
finally:
video_encoder_lock.release()