elastic_play

gistfile1.txt

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    "#### Problem definition:\n",
    "\n",
    "Given a video at duration: $ D $,\n",
    "\n",
    "By running a shot-detection algorithm, we get the information of n shots: $ v_1, v_2, v_3...v_n$ . (each shot length varies from 2 sec - 5 sec.)\n",
    "\n",
    "Based on the computer vision algorithm, we also have the score of each shot: $ s_1, s_2, s_3, ...s_n $ and the duration of each shot: $ d_1, d_2, .... d_n $.\n",
    "\n"
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    "From the prior research, people have reported the correlation between the playback rate and the understand rate:\n",
    "\n",
    "Understand rate is referenced to the ratio of people can well understand the content for certain speed.\n",
    "\n",
    "\n",
    "for silent parts: $ u_s = -0.1 * (v_s -1 ) + 1 $ \n",
    "\n",
    "for non-silent parts: $ u_n = - (v_n - 1) + 1 $"
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    "\n",
    "Our preliminary study shows users prefer a universal constant speed across the video.\n",
    "\n",
    "Based on this finding, we maintain a universal $v_s$ and $v_n$ for all the shots.\n",
    "\n",
    "Meanwhile, we want to maintain an equal understanding for the silent parts and non-silent parts. \n"
   ]
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    "As we speed up the content, the actual score ${s_k}^*$ can be perceived by the user is:\n",
    "\n",
    "${s_k}^* = u_s * {s_k} $\n",
    "\n",
    "The actual length for each shot is:\n",
    "\n",
    "$ {d_k}^* = \\frac{{d\\_{ks}}}{v_s} + \\frac{{d\\_{kn}}}{v_n} $"
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    "The final question is:\n",
    "\n",
    "How can we maximum the total scores of different shots under a certain time budget?"
   ]
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    "#### Solution description:\n"
   ]
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    "Run a dynamic programming over the different speedup case.\n",
    "- $v_s$ range: 1x-6x; $v_n$ range: 1x-1.5x.  \n",
    "- speed up step count: 100.\n",
    "- actual speedup case [$v_s, v_n$]: [1x, 1x], [1.5x, 1.05x], [2x, 1.1x].... [6x, 1.5x]\n",
    "    \n",
    "    \n",
    "Maintain a hashmap of dynamic map for that 10 speedup case.\n",
    "\n",
    "\n",
    "For any time budget, we iterate different speedup cases and find the optimal solution."
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   "source": [
    "#### Change to the evaluation:\n"
   ]
  },
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "- how should we evaluate the different recall in the current case?\n",
    "\n",
    "- what's the ground truth strategy for different time budgets now?"
   ]
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