def algorithm1(dash):
max_buffer = dash.max_buffer
r = max_buffer * 0.3
cu = max_buffer * (0.9 - 0.3)
T = dash.get_throughput()
quality = dash.quality
buffer_len = dash.buffer_len
new_quality = quality
max_quality = len(dash.mpd["bitrates"])
next_chunks_size = dash.get_chunks_size()
duration = dash.segment_len
ref = 1
for i in range(1, max_quality):
if next_chunks_size[i] / duration > T:
ref = i - 1
break
if buffer_len <= r :
for i in range(1, max_quality):
if next_chunks_size[i] > (duration - buffer_len) * T:
tmp = i - 1
break
new_quality = max(tmp,1)
elif buffer_len >= (r + cu) :
new_quality = max_quality
else:
new_quality = ref
dash.select(new_quality)
def Init(dash):
dash.bitrate = dash.mpd["bitrates"][0]
init_size = dash.mpd[dash.bitrate][0]
while init_size > 0:
init_size = init_size - dash.sim_inteval * dash.get_throughput()
dash.time = dash.time + dash.sim_inteval
#dash.log(str(1) + " Downloaded!")
dash.buffer_len = dash.segment_len
#dash.log("Buffer Level: " + str(dash.buffer_len))
dash.chunk_index = dash.chunk_index + 1
dash.select(1)
def BBA1(dash):
max_buffer = dash.max_buffer
#r = max_buffer * 0.3
#cu = max_buffer * (0.9 - 0.3)
r = dash.r
cu = dash.cu
T = dash.get_throughput()
quality = dash.quality
buffer_len = dash.buffer_len
new_quality = quality
max_quality = len(dash.mpd["bitrates"])
last_chunk_index = (dash.chunk_index - 1)
last_dltime = dash.dltime[last_chunk_index]
duration = dash.segment_len
r = r + (last_dltime - duration)
if r < 2 * duration :
r = 2 * duration
elif r > 0.5 * max_buffer :
r = 0.5 * max_buffer
dash.r = r
quality_plus = quality
quality_minus = quality
if quality > max_quality:
quality_plus = max_quality
else:
quality_plus = quality + 1
if quality <= 1 :
quality_minus = 1
else:
quality_minus = quality - 1
if buffer_len <= r :
new_quality = 1
elif buffer_len >= (r + cu) :
new_quality = max_quality
tmp = 1 + (buffer_len - r) * (max_quality - 1) / cu
if tmp >= quality_plus :
new_quality = math.floor(tmp)
elif tmp <= quality_minus:
new_quality = math.ceil(tmp)
else:
new_quality = quality
dash.select(new_quality)
def PBAC2(dash):
max_buffer = dash.max_buffer
r = max_buffer * 0.3
cu = max_buffer * (0.9 - 0.3)
T = dash.get_throughput()
quality = dash.quality
buffer_len = dash.buffer_len
new_quality = quality
max_quality = len(dash.mpd["bitrates"])
next_chunks_size = dash.get_chunks_size()
duration = dash.segment_len
ref = 1
for i in range(1, max_quality):
if next_chunks_size[i] / duration > T:
ref = i - 1
break
if buffer_len <= r :
ref = max(ref-1,1)
if ref < quality:
for i in range(1, max_quality):
if next_chunks_size[i] > (duration - buffer_len) * T:
tmp = i - 1
break
new_quality = max(tmp,1)
else:
new_quality = ref
elif buffer_len >= (r + cu) :
new_quality = max_quality
#new_quality = max(ref,quality)
else:
if ref < quality :
new_quality = quality
else:
buffergap = duration * (T/next_chunks_size[ref]-1)
bufferemp = max_buffer - buffer_len
if buffergap > 0.15 * bufferemp:
new_quality = ref
else:
new_quality = ref - 1
dash.select(new_quality)
def BBA(dash):
max_buffer = dash.max_buffer
#r = max_buffer * 0.3
#cu = max_buffer * (0.9 - 0.3)
r = dash.r
cu = dash.cu
T = dash.get_throughput()
quality = dash.quality
buffer_len = dash.buffer_len
new_quality = quality
max_quality = len(dash.mpd["bitrates"])
quality_plus = quality
quality_minus = quality
if quality > max_quality:
quality_plus = max_quality
else:
quality_plus = quality + 1
if quality <= 1 :
quality_minus = 1
else:
quality_minus = quality - 1
if buffer_len <= r :
new_quality = 1
elif buffer_len >= (r + cu) :
new_quality = max_quality
tmp = 1 + (buffer_len - r) * (max_quality - 1) / cu
if tmp >= quality_plus :
new_quality = math.floor(tmp)
elif tmp <= quality_minus:
new_quality = math.ceil(tmp)
else:
new_quality = quality
dash.select(new_quality)
def BBA2(dash):
max_buffer = dash.max_buffer
#r = max_buffer * 0.3
#cu = max_buffer * (0.9 - 0.3)
r = dash.r
cu = dash.cu
T = dash.get_throughput()
quality = dash.quality
buffer_len = dash.buffer_len
new_quality = quality
new_quality_startup = 1
max_quality = len(dash.mpd["bitrates"])
last_chunk_index = (dash.chunk_index - 1)
last_dltime = dash.dltime[last_chunk_index]
duration = dash.segment_len
last_buffer_len = dash.last_buffer_len
r = r + (last_dltime - duration)
if r < 2 * duration :
r = 2 * duration
elif r > 0.5 * max_buffer :
r = 0.5 * max_buffer
dash.r = r
if buffer_len < last_buffer_len :
dash.startup = 0
if dash.startup == 1 :
if buffer_len < r :
if duration > dash.bba2_threshold * last_dltime:
new_quality_startup = quality + 1
dash.bba2_threshold = dash.bba2_threshold - 1
else:
new_quality_startup = quality
else:
dash.bba2_threshold = 2
if duration > dash.bba2_threshold * last_dltime:
new_quality_startup = quality + 1
else:
new_quality_startup = quality
quality_plus = quality
quality_minus = quality
if quality > max_quality:
quality_plus = max_quality
else:
quality_plus = quality + 1
if quality <= 1 :
quality_minus = 1
else:
quality_minus = quality - 1
if buffer_len <= r :
new_quality = 1
elif buffer_len >= (r + cu) :
new_quality = max_quality
tmp = 1 + (buffer_len - r) * (max_quality - 1) / cu
if tmp >= quality_plus :
new_quality = math.floor(tmp)
elif tmp <= quality_minus:
new_quality = math.ceil(tmp)
else:
new_quality = quality
if new_quality > new_quality_startup :
dash.startup = 0
else:
new_quality = new_quality_startup
dash.select(new_quality)