{
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  "sourcePath": "src/main/data/docs",
  "docId": "10.5594-J13463",
  "document": {
    "abbrevTitle": "J SMPTE",
    "abbrevTitle$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "abstract": "Digital television may effectively serve as the means to store, process and control color television signals within a broadcast plant. Pulse code modulation (PCM) involves the periodic amplitude sampling of a video signal and the conversion of each sample into a binary number of n bits. The PCM signal bit stream can be in n parallel channels or be time multiplexed into a single channel. In either case the total bit rate equals n times the encoding rate. We desire to minimize the bit rate in order to save circuit elements and bandwidth, consistent of course with acceptable picture quality. A series of subjective tests was conducted to determine the importance of various parameters when PCM encoding an NTSC, 525-line, 60-field, composite television signal. Among these parameters are: (1) the number of amplitude levels being sampled that, in turn, define the n-bit digital word; (2) the encoding rate, both locked and unlocked with respect to the 3.58-MHz color subcarrier; and (3) the role of dither consisting of coherent square waves and weighted noise. The test setup consisted of a color film camera, encoding rate generators, dither generators, A/D and D/A converters, color and monochrome monitors. A test panel of experienced viewers examined the pictures in a controlled environment and rated each picture on a stepped acceptance scale. We concluded that NTSC television pictures that had been encoded with 6 or more bits per codeword suffered negligible impairment. The encode rate should be phase coherent with the color subcarrier in order to avoid beats in the picture. Dither signals did not make any improvement in picture quality except to mask contours during 4- or 5-bit encoding.",
    "abstract$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "articleType": "research-article",
    "articleType$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "authors": [
      "A. A. Goldberg"
    ],
    "authors$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "copyright": {
      "holder": "Society of Motion Picture and Television Engineers, Inc.",
      "holder$meta": {
        "confidence": "high",
        "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
        "source": "parsed",
        "updated": "2026-05-22T20:40:11.684Z",
        "version": "smpte-journal-article-nlm@v1"
      },
      "year": "1973",
      "year$meta": {
        "confidence": "high",
        "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
        "source": "parsed",
        "updated": "2026-05-22T20:40:11.684Z",
        "version": "smpte-journal-article-nlm@v1"
      }
    },
    "copyright$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "docId": "10.5594-J13463",
    "docId$meta": {
      "confidence": "high",
      "note": "Derived from DOI 10.5594/J13463",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "docLabel": "Journal of the SMPTE ( Volume: 82, Issue: 8, August 1973)",
    "docLabel$meta": {
      "confidence": "medium",
      "note": "Composed from venue title, volume/issue and date",
      "source": "inferred",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "docTitle": "PCM Encoded NTSC Color Television Subjective Tests",
    "docTitle$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "docType": "Journal Article",
    "docType$meta": {
      "confidence": "high",
      "note": "NLM <article> — SMPTE journal paper",
      "source": "inferred",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "doi": "10.5594/J13463",
    "doi$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "href": "https://doi.org/10.5594/J13463",
    "href$meta": {
      "confidence": "high",
      "note": "Constructed from DOI 10.5594/J13463",
      "source": "inferred",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "issn": {
      "print": "0361-4573",
      "print$meta": {
        "confidence": "high",
        "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
        "source": "parsed",
        "updated": "2026-05-22T20:40:11.684Z",
        "version": "smpte-journal-article-nlm@v1"
      }
    },
    "issn$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "journalAcronym": "MIJR",
    "journalAcronym$meta": {
      "confidence": "high",
      "note": "Parsed from journal_metadata XML (_source/SMPTE/APTARA/DL Project Files/08202015 BACKFILE JOURNAL FRESH/smptej_82_8/MIJR15Vol82No8.xml)",
      "source": "parsed",
      "updated": "2026-06-16T18:14:32.753Z",
      "version": "smpte-journal-issue-xml@v1"
    },
    "number": "8",
    "number$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "pages": "649–654",
    "pages$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "publicationDate": "1973-08-01",
    "publicationDate$meta": {
      "confidence": "high",
      "note": "Day absent in NLM source — padded to 01",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "publisher": "SMPTE",
    "publisher$meta": {
      "confidence": "high",
      "note": "Normalised to registry \"SMPTE\" convention from NLM publisher-name (The Society of Motion Picture and Television Engineers)",
      "source": "inferred",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "publisherLocation": {
      "city": "White Plains, NY",
      "city$meta": {
        "confidence": "high",
        "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
        "source": "parsed",
        "updated": "2026-05-22T20:40:11.684Z",
        "version": "smpte-journal-article-nlm@v1"
      },
      "country": "USA",
      "country$meta": {
        "confidence": "high",
        "note": "Parsed from journal_metadata XML (_source/SMPTE/APTARA/DL Project Files/08202015 BACKFILE JOURNAL FRESH/smptej_82_8/MIJR15Vol82No8.xml)",
        "source": "parsed",
        "updated": "2026-06-16T18:14:32.753Z",
        "version": "smpte-journal-issue-xml@v1"
      }
    },
    "publisherLocation$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    },
    "status": {
      "active": true,
      "active$meta": {
        "confidence": "medium",
        "note": "No explicit status in NLM source — journal papers default active",
        "source": "inferred",
        "updated": "2026-05-22T20:40:11.684Z",
        "version": "smpte-journal-article-nlm@v1"
      }
    },
    "volume": "82",
    "volume$meta": {
      "confidence": "high",
      "note": "Parsed from NLM article XML (_source/SMPTE/HIGHWIRE/Source Bak/smptej/10.5594_J13463.xml)",
      "source": "parsed",
      "updated": "2026-05-22T20:40:11.684Z",
      "version": "smpte-journal-article-nlm@v1"
    }
  }
}