File size: 7,331 Bytes
b9b1b10
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
import re
import torch
import clip
import numpy as np
from numpy.linalg import norm
from PIL import Image

def get_quality_hint_from_metadata(mos, width, height, bitrate, bitdepth, framerate, quality_hints):
    hint = []
    if mos > 5:
        mos = (mos / 100) * 5
    if mos >= 4.5:
        hint.append(quality_hints["mos"]["excellent"])
    elif 3.5 <= mos < 4.5:
        hint.append(quality_hints["mos"]["good"])
    elif 2.5 <= mos < 3.5:
        hint.append(quality_hints["mos"]["fair"])
    elif 1.5 <= mos < 2.5:
        hint.append(quality_hints["mos"]["bad"])
    else:
        hint.append(quality_hints["mos"]["poor"])

    res = width * height
    if res < 640 * 480:
        hint.append(quality_hints["resolution"]["low"])
    elif res < 1280 * 720:
        hint.append(quality_hints["resolution"]["sd"])
    else:
        hint.append(quality_hints["resolution"]["hd"])
    if bitrate < 500_000:
        hint.append(quality_hints["bitrate"]["low"])
    elif bitrate < 1_000_000:
        hint.append(quality_hints["bitrate"]["medium"])
    else:
        hint.append(quality_hints["bitrate"]["high"])

    if 0 < bitdepth <= 8:
        hint.append(quality_hints["bitdepth"]["low"])
    elif bitdepth == 0:
        hint.append(quality_hints["bitdepth"]["standard"])
    else:
        hint.append(quality_hints["bitdepth"]["high"])
    if framerate < 24:
        hint.append(quality_hints["framerate"]["low"])
    elif framerate > 60:
        hint.append(quality_hints["framerate"]["high"])
    else:
        hint.append(quality_hints["framerate"]["standard"])
    return " ".join(hint)

def generate_caption(blip_processor, blip_model, device, image, prompt):
    inputs = blip_processor(image, prompt, return_tensors="pt").to(device)
    generated_ids = blip_model.generate(**inputs, max_new_tokens=50)
    caption = blip_processor.decode(generated_ids[0], skip_special_tokens=True)
    return caption

def tensor_to_pil(image_tensor):
    if isinstance(image_tensor, torch.Tensor):
        arr = image_tensor.cpu().numpy()
        if arr.ndim == 4 and arr.shape[0] == 1:
            arr = arr[0]  # remove batch dimension
        arr = arr.astype('uint8')
    return Image.fromarray(arr)

def extract_semantic_captions(blip_processor, blip_model, curr_frame, frag_residual, frag_frame, prompts, device, metadata=None, use_metadata_prompt=False):
    quality_prompt_base = prompts["quality_prompt_base"]
    residual_prompt = prompts["residual_prompt"]
    frag_prompt = prompts["frag_prompt"]

    quality_hint = ""
    if use_metadata_prompt and metadata:
        mos, width, height, bitrate, bitdepth, framerate = metadata
        quality_hint = get_quality_hint_from_metadata(mos, width, height, bitrate, bitdepth, framerate, quality_hints=prompts["quality_hints"])

    prompt_hints = []
    if quality_hint:
        prompt_hints.append(quality_hint)

    quality_prompt = "\n\n".join(prompt_hints + [quality_prompt_base])
    fragment_prompt = "\n\n".join(prompt_hints)
    # print('content_prompt:', content_prompt)
    # print('quality_prompt:', quality_prompt)
    # print('residual_prompt:', fragment_prompt + "\n\n" + residual_prompt)
    # print('frame_fragment_prompt:', fragment_prompt + "\n\n" + frag_prompt)

    captions = {
        "curr_frame_quality": generate_caption(blip_processor, blip_model, device, curr_frame, prompt=quality_prompt),
        "frag_residual": generate_caption(blip_processor, blip_model, device, frag_residual, prompt=(fragment_prompt + "\n\n" + residual_prompt)),
        "frag_frame": generate_caption(blip_processor, blip_model, device, frag_frame, prompt=(fragment_prompt + "\n\n" + frag_prompt))
    }
    return captions

def clean_caption_text(text):
    text = re.sub(r"- .*?stock videos & royalty-free footage", "", text)
    text = re.sub(r"\s+", " ", text)
    return text.strip()

def dedup_keywords(text, split_tokens=[",", ".", ";"]):
    for token in split_tokens:
        text = text.replace(token, ",")
    parts = [p.strip().lower() for p in text.split(",") if p.strip()]
    seen = set()
    unique_parts = []
    for part in parts:
        if part not in seen:
            unique_parts.append(part)
            seen.add(part)
    return " ".join(unique_parts)  # good for embedding

def get_clip_text_embedding(clip_model, device, text):
    text_tokens = clip.tokenize([text]).to(device)
    with torch.no_grad():
        with torch.amp.autocast(device_type='cuda'):
            text_features = clip_model.encode_text(text_tokens)
            text_features = text_features / text_features.norm(dim=-1, keepdim=True)
    return text_features.squeeze()

def get_clip_image_embedding(clip_model, clip_preprocess, device, image):
    image_input = clip_preprocess(image).unsqueeze(0).to(device)
    with torch.no_grad():
        with torch.amp.autocast(device_type='cuda'):
            image_features = clip_model.encode_image(image_input)
            image_features = image_features / image_features.norm(dim=-1, keepdim=True)
    return image_features.squeeze()

def extract_semantic_embeddings(clip_model, clip_preprocess, device, curr_frame, captions):
    if not isinstance(curr_frame, Image.Image):
        curr_frame = Image.fromarray(curr_frame)

    quality_caption = dedup_keywords(clean_caption_text(captions["curr_frame_quality"]))
    artifact_caption_1 = dedup_keywords(clean_caption_text(captions["frag_residual"]))
    artifact_caption_2 = dedup_keywords(clean_caption_text(captions["frag_frame"]))
    artifact_caption = dedup_keywords(f"{artifact_caption_1}, {artifact_caption_2}")

    image_embed = get_clip_image_embedding(clip_model, clip_preprocess, device, curr_frame)
    quality_embed = get_clip_text_embedding(clip_model, device, quality_caption)
    artifact_embed = get_clip_text_embedding(clip_model, device, artifact_caption)
    return image_embed, quality_embed, artifact_embed

def extract_features_clip_embed(frames_info, metadata, clip_model, clip_preprocess, blip_processor, blip_model, prompts, device):
    feature_image_embed = []
    feature_quality_embed = []
    feature_artifact_embed = []
    for i, (curr_frame, frag_residual, frag_frame) in enumerate(frames_info):
        curr_frame = tensor_to_pil(curr_frame)
        frag_residual = tensor_to_pil(frag_residual)
        frag_frame = tensor_to_pil(frag_frame)

        captions = extract_semantic_captions(
            blip_processor, blip_model,
            curr_frame, frag_residual, frag_frame, prompts,
            device,
            metadata=metadata,
            use_metadata_prompt=True,
        )
        image_embed, quality_embed, artifact_embed = extract_semantic_embeddings(clip_model, clip_preprocess, device, curr_frame, captions)
        feature_image_embed.append(image_embed)
        feature_quality_embed.append(quality_embed)
        feature_artifact_embed.append(artifact_embed)

    # concatenate features
    image_embedding = torch.stack(feature_image_embed, dim=0)
    quality_embedding = torch.stack(feature_quality_embed, dim=0)
    artifact_embedding = torch.stack(feature_artifact_embed, dim=0)
    # print("image_embedding.shape:", image_embedding.shape, "quality_embedding.shape:", quality_embedding.shape, "artifact_embedding.shape:", artifact_embedding.shape)
    return image_embedding, quality_embedding, artifact_embedding