mirror of
https://github.com/FFmpeg/FFmpeg.git
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672 lines
21 KiB
C
672 lines
21 KiB
C
/*
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* Closed Caption Decoding
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* Copyright (c) 2015 Anshul Maheshwari
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "avcodec.h"
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#include "ass.h"
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#include "libavutil/opt.h"
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#define SCREEN_ROWS 15
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#define SCREEN_COLUMNS 32
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#define SET_FLAG(var, val) ( (var) |= ( 1 << (val)) )
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#define UNSET_FLAG(var, val) ( (var) &= ~( 1 << (val)) )
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#define CHECK_FLAG(var, val) ( (var) & ( 1 << (val)) )
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static const AVRational ass_tb = {1, 100};
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/*
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* TODO list
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* 1) handle font and color completely
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*/
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enum cc_mode {
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CCMODE_POPON,
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CCMODE_PAINTON,
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CCMODE_ROLLUP,
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CCMODE_TEXT,
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};
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enum cc_color_code {
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CCCOL_WHITE,
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CCCOL_GREEN,
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CCCOL_BLUE,
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CCCOL_CYAN,
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CCCOL_RED,
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CCCOL_YELLOW,
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CCCOL_MAGENTA,
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CCCOL_USERDEFINED,
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CCCOL_BLACK,
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CCCOL_TRANSPARENT,
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};
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enum cc_font {
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CCFONT_REGULAR,
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CCFONT_ITALICS,
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CCFONT_UNDERLINED,
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CCFONT_UNDERLINED_ITALICS,
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};
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static const unsigned char pac2_attribs[32][3] = // Color, font, ident
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{
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{ CCCOL_WHITE, CCFONT_REGULAR, 0 }, // 0x40 || 0x60
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{ CCCOL_WHITE, CCFONT_UNDERLINED, 0 }, // 0x41 || 0x61
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{ CCCOL_GREEN, CCFONT_REGULAR, 0 }, // 0x42 || 0x62
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{ CCCOL_GREEN, CCFONT_UNDERLINED, 0 }, // 0x43 || 0x63
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{ CCCOL_BLUE, CCFONT_REGULAR, 0 }, // 0x44 || 0x64
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{ CCCOL_BLUE, CCFONT_UNDERLINED, 0 }, // 0x45 || 0x65
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{ CCCOL_CYAN, CCFONT_REGULAR, 0 }, // 0x46 || 0x66
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{ CCCOL_CYAN, CCFONT_UNDERLINED, 0 }, // 0x47 || 0x67
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{ CCCOL_RED, CCFONT_REGULAR, 0 }, // 0x48 || 0x68
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{ CCCOL_RED, CCFONT_UNDERLINED, 0 }, // 0x49 || 0x69
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{ CCCOL_YELLOW, CCFONT_REGULAR, 0 }, // 0x4a || 0x6a
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{ CCCOL_YELLOW, CCFONT_UNDERLINED, 0 }, // 0x4b || 0x6b
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{ CCCOL_MAGENTA, CCFONT_REGULAR, 0 }, // 0x4c || 0x6c
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{ CCCOL_MAGENTA, CCFONT_UNDERLINED, 0 }, // 0x4d || 0x6d
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{ CCCOL_WHITE, CCFONT_ITALICS, 0 }, // 0x4e || 0x6e
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{ CCCOL_WHITE, CCFONT_UNDERLINED_ITALICS, 0 }, // 0x4f || 0x6f
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{ CCCOL_WHITE, CCFONT_REGULAR, 0 }, // 0x50 || 0x70
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{ CCCOL_WHITE, CCFONT_UNDERLINED, 0 }, // 0x51 || 0x71
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{ CCCOL_WHITE, CCFONT_REGULAR, 4 }, // 0x52 || 0x72
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{ CCCOL_WHITE, CCFONT_UNDERLINED, 4 }, // 0x53 || 0x73
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{ CCCOL_WHITE, CCFONT_REGULAR, 8 }, // 0x54 || 0x74
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{ CCCOL_WHITE, CCFONT_UNDERLINED, 8 }, // 0x55 || 0x75
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{ CCCOL_WHITE, CCFONT_REGULAR, 12 }, // 0x56 || 0x76
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{ CCCOL_WHITE, CCFONT_UNDERLINED, 12 }, // 0x57 || 0x77
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{ CCCOL_WHITE, CCFONT_REGULAR, 16 }, // 0x58 || 0x78
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{ CCCOL_WHITE, CCFONT_UNDERLINED, 16 }, // 0x59 || 0x79
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{ CCCOL_WHITE, CCFONT_REGULAR, 20 }, // 0x5a || 0x7a
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{ CCCOL_WHITE, CCFONT_UNDERLINED, 20 }, // 0x5b || 0x7b
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{ CCCOL_WHITE, CCFONT_REGULAR, 24 }, // 0x5c || 0x7c
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{ CCCOL_WHITE, CCFONT_UNDERLINED, 24 }, // 0x5d || 0x7d
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{ CCCOL_WHITE, CCFONT_REGULAR, 28 }, // 0x5e || 0x7e
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{ CCCOL_WHITE, CCFONT_UNDERLINED, 28 } // 0x5f || 0x7f
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/* total 32 entries */
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};
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struct Screen {
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/* +1 is used to compensate null character of string */
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uint8_t characters[SCREEN_ROWS][SCREEN_COLUMNS+1];
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uint8_t colors[SCREEN_ROWS][SCREEN_COLUMNS+1];
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uint8_t fonts[SCREEN_ROWS][SCREEN_COLUMNS+1];
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/*
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* Bitmask of used rows; if a bit is not set, the
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* corresponding row is not used.
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* for setting row 1 use row | (1 << 0)
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* for setting row 15 use row | (1 << 14)
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*/
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int16_t row_used;
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};
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typedef struct CCaptionSubContext {
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AVClass *class;
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int real_time;
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struct Screen screen[2];
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int active_screen;
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uint8_t cursor_row;
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uint8_t cursor_column;
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uint8_t cursor_color;
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uint8_t cursor_font;
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AVBPrint buffer;
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int buffer_changed;
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int rollup;
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enum cc_mode mode;
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int64_t start_time;
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/* visible screen time */
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int64_t startv_time;
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int64_t end_time;
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int screen_touched;
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int64_t last_real_time;
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char prev_cmd[2];
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/* buffer to store pkt data */
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AVBufferRef *pktbuf;
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} CCaptionSubContext;
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static av_cold int init_decoder(AVCodecContext *avctx)
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{
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int ret;
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CCaptionSubContext *ctx = avctx->priv_data;
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av_bprint_init(&ctx->buffer, 0, AV_BPRINT_SIZE_UNLIMITED);
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/* taking by default roll up to 2 */
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ctx->mode = CCMODE_ROLLUP;
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ctx->rollup = 2;
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ret = ff_ass_subtitle_header(avctx, "Monospace",
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ASS_DEFAULT_FONT_SIZE,
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ASS_DEFAULT_COLOR,
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ASS_DEFAULT_BACK_COLOR,
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ASS_DEFAULT_BOLD,
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ASS_DEFAULT_ITALIC,
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ASS_DEFAULT_UNDERLINE,
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3,
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ASS_DEFAULT_ALIGNMENT);
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if (ret < 0) {
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return ret;
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}
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/* allocate pkt buffer */
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ctx->pktbuf = av_buffer_alloc(128);
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if (!ctx->pktbuf) {
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ret = AVERROR(ENOMEM);
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}
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return ret;
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}
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static av_cold int close_decoder(AVCodecContext *avctx)
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{
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CCaptionSubContext *ctx = avctx->priv_data;
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av_bprint_finalize(&ctx->buffer, NULL);
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av_buffer_unref(&ctx->pktbuf);
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return 0;
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}
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static void flush_decoder(AVCodecContext *avctx)
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{
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CCaptionSubContext *ctx = avctx->priv_data;
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ctx->screen[0].row_used = 0;
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ctx->screen[1].row_used = 0;
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ctx->prev_cmd[0] = 0;
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ctx->prev_cmd[1] = 0;
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ctx->mode = CCMODE_ROLLUP;
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ctx->rollup = 2;
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ctx->cursor_row = 0;
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ctx->cursor_column = 0;
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ctx->cursor_font = 0;
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ctx->cursor_color = 0;
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ctx->active_screen = 0;
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ctx->last_real_time = 0;
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ctx->screen_touched = 0;
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ctx->buffer_changed = 0;
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av_bprint_clear(&ctx->buffer);
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}
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/**
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* @param ctx closed caption context just to print log
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*/
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static int write_char(CCaptionSubContext *ctx, struct Screen *screen, char ch)
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{
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uint8_t col = ctx->cursor_column;
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char *row = screen->characters[ctx->cursor_row];
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char *font = screen->fonts[ctx->cursor_row];
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if (col < SCREEN_COLUMNS) {
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row[col] = ch;
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font[col] = ctx->cursor_font;
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if (ch) ctx->cursor_column++;
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return 0;
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}
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/* We have extra space at end only for null character */
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else if (col == SCREEN_COLUMNS && ch == 0) {
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row[col] = ch;
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return 0;
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}
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else {
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av_log(ctx, AV_LOG_WARNING, "Data Ignored since exceeding screen width\n");
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return AVERROR_INVALIDDATA;
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}
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}
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/**
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* This function after validating parity bit, also remove it from data pair.
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* The first byte doesn't pass parity, we replace it with a solid blank
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* and process the pair.
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* If the second byte doesn't pass parity, it returns INVALIDDATA
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* user can ignore the whole pair and pass the other pair.
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*/
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static int validate_cc_data_pair(uint8_t *cc_data_pair)
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{
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uint8_t cc_valid = (*cc_data_pair & 4) >>2;
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uint8_t cc_type = *cc_data_pair & 3;
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if (!cc_valid)
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return AVERROR_INVALIDDATA;
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// if EIA-608 data then verify parity.
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if (cc_type==0 || cc_type==1) {
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if (!av_parity(cc_data_pair[2])) {
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return AVERROR_INVALIDDATA;
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}
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if (!av_parity(cc_data_pair[1])) {
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cc_data_pair[1]=0x7F;
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}
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}
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//Skip non-data
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if ((cc_data_pair[0] == 0xFA || cc_data_pair[0] == 0xFC || cc_data_pair[0] == 0xFD)
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&& (cc_data_pair[1] & 0x7F) == 0 && (cc_data_pair[2] & 0x7F) == 0)
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return AVERROR_PATCHWELCOME;
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//skip 708 data
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if (cc_type == 3 || cc_type == 2)
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return AVERROR_PATCHWELCOME;
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/* remove parity bit */
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cc_data_pair[1] &= 0x7F;
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cc_data_pair[2] &= 0x7F;
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return 0;
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}
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static struct Screen *get_writing_screen(CCaptionSubContext *ctx)
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{
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switch (ctx->mode) {
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case CCMODE_POPON:
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// use Inactive screen
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return ctx->screen + !ctx->active_screen;
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case CCMODE_PAINTON:
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case CCMODE_ROLLUP:
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case CCMODE_TEXT:
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// use active screen
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return ctx->screen + ctx->active_screen;
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}
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/* It was never an option */
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return NULL;
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}
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static void roll_up(CCaptionSubContext *ctx)
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{
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struct Screen *screen;
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int i, keep_lines;
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if (ctx->mode == CCMODE_TEXT)
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return;
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screen = get_writing_screen(ctx);
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/* +1 signify cursor_row starts from 0
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* Can't keep lines less then row cursor pos
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*/
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keep_lines = FFMIN(ctx->cursor_row + 1, ctx->rollup);
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for (i = 0; i < SCREEN_ROWS; i++) {
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if (i > ctx->cursor_row - keep_lines && i <= ctx->cursor_row)
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continue;
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UNSET_FLAG(screen->row_used, i);
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}
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for (i = 0; i < keep_lines && screen->row_used; i++) {
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const int i_row = ctx->cursor_row - keep_lines + i + 1;
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memcpy(screen->characters[i_row], screen->characters[i_row+1], SCREEN_COLUMNS);
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memcpy(screen->colors[i_row], screen->colors[i_row+1], SCREEN_COLUMNS);
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memcpy(screen->fonts[i_row], screen->fonts[i_row+1], SCREEN_COLUMNS);
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if (CHECK_FLAG(screen->row_used, i_row + 1))
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SET_FLAG(screen->row_used, i_row);
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}
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UNSET_FLAG(screen->row_used, ctx->cursor_row);
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}
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static int capture_screen(CCaptionSubContext *ctx)
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{
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int i;
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struct Screen *screen = ctx->screen + ctx->active_screen;
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enum cc_font prev_font = CCFONT_REGULAR;
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av_bprint_clear(&ctx->buffer);
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for (i = 0; screen->row_used && i < SCREEN_ROWS; i++)
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{
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if (CHECK_FLAG(screen->row_used, i)) {
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const char *row = screen->characters[i];
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const char *font = screen->fonts[i];
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int j = 0;
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/* skip leading space */
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while (row[j] == ' ')
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j++;
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for (; j < SCREEN_COLUMNS; j++) {
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const char *e_tag = "", *s_tag = "";
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if (row[j] == 0)
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break;
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if (prev_font != font[j]) {
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switch (prev_font) {
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case CCFONT_ITALICS:
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e_tag = "{\\i0}";
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break;
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case CCFONT_UNDERLINED:
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e_tag = "{\\u0}";
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break;
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case CCFONT_UNDERLINED_ITALICS:
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e_tag = "{\\u0}{\\i0}";
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break;
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}
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switch (font[j]) {
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case CCFONT_ITALICS:
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s_tag = "{\\i1}";
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break;
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case CCFONT_UNDERLINED:
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s_tag = "{\\u1}";
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break;
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case CCFONT_UNDERLINED_ITALICS:
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s_tag = "{\\u1}{\\i1}";
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break;
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}
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}
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prev_font = font[j];
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av_bprintf(&ctx->buffer, "%s%s%c", e_tag, s_tag, row[j]);
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}
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av_bprintf(&ctx->buffer, "\\N");
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}
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}
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if (!av_bprint_is_complete(&ctx->buffer))
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return AVERROR(ENOMEM);
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if (screen->row_used && ctx->buffer.len >= 2) {
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ctx->buffer.len -= 2;
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ctx->buffer.str[ctx->buffer.len] = 0;
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}
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ctx->buffer_changed = 1;
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return 0;
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}
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static int reap_screen(CCaptionSubContext *ctx, int64_t pts)
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{
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ctx->start_time = ctx->startv_time;
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ctx->startv_time = pts;
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ctx->end_time = pts;
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return capture_screen(ctx);
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}
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static void handle_textattr(CCaptionSubContext *ctx, uint8_t hi, uint8_t lo)
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{
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int i = lo - 0x20;
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struct Screen *screen = get_writing_screen(ctx);
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if (i >= 32)
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return;
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ctx->cursor_color = pac2_attribs[i][0];
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ctx->cursor_font = pac2_attribs[i][1];
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SET_FLAG(screen->row_used, ctx->cursor_row);
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write_char(ctx, screen, ' ');
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}
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static void handle_pac(CCaptionSubContext *ctx, uint8_t hi, uint8_t lo)
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{
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static const int8_t row_map[] = {
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11, -1, 1, 2, 3, 4, 12, 13, 14, 15, 5, 6, 7, 8, 9, 10
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};
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const int index = ( (hi<<1) & 0x0e) | ( (lo>>5) & 0x01 );
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struct Screen *screen = get_writing_screen(ctx);
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int indent, i;
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if (row_map[index] <= 0) {
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av_log(ctx, AV_LOG_DEBUG, "Invalid pac index encountered\n");
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return;
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}
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lo &= 0x1f;
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ctx->cursor_row = row_map[index] - 1;
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ctx->cursor_color = pac2_attribs[lo][0];
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ctx->cursor_font = pac2_attribs[lo][1];
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ctx->cursor_column = 0;
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indent = pac2_attribs[lo][2];
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for (i = 0; i < indent; i++) {
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write_char(ctx, screen, ' ');
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}
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}
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/**
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* @param pts it is required to set end time
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*/
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static void handle_edm(CCaptionSubContext *ctx, int64_t pts)
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{
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struct Screen *screen = ctx->screen + ctx->active_screen;
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// In buffered mode, keep writing to screen until it is wiped.
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// Before wiping the display, capture contents to emit subtitle.
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if (!ctx->real_time)
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reap_screen(ctx, pts);
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screen->row_used = 0;
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// In realtime mode, emit an empty caption so the last one doesn't
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// stay on the screen.
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if (ctx->real_time)
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reap_screen(ctx, pts);
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}
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static void handle_eoc(CCaptionSubContext *ctx, int64_t pts)
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{
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// In buffered mode, we wait til the *next* EOC and
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// reap what was already on the screen since the last EOC.
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if (!ctx->real_time)
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handle_edm(ctx,pts);
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ctx->active_screen = !ctx->active_screen;
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ctx->cursor_column = 0;
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// In realtime mode, we display the buffered contents (after
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// flipping the buffer to active above) as soon as EOC arrives.
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if (ctx->real_time)
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reap_screen(ctx, pts);
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}
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static void handle_delete_end_of_row(CCaptionSubContext *ctx, char hi, char lo)
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{
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struct Screen *screen = get_writing_screen(ctx);
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write_char(ctx, screen, 0);
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}
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static void handle_char(CCaptionSubContext *ctx, char hi, char lo, int64_t pts)
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{
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struct Screen *screen = get_writing_screen(ctx);
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SET_FLAG(screen->row_used, ctx->cursor_row);
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write_char(ctx, screen, hi);
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if (lo) {
|
|
write_char(ctx, screen, lo);
|
|
}
|
|
write_char(ctx, screen, 0);
|
|
|
|
if (ctx->mode != CCMODE_POPON)
|
|
ctx->screen_touched = 1;
|
|
|
|
/* reset prev command since character can repeat */
|
|
ctx->prev_cmd[0] = 0;
|
|
ctx->prev_cmd[1] = 0;
|
|
if (lo)
|
|
ff_dlog(ctx, "(%c,%c)\n", hi, lo);
|
|
else
|
|
ff_dlog(ctx, "(%c)\n", hi);
|
|
}
|
|
|
|
static void process_cc608(CCaptionSubContext *ctx, int64_t pts, uint8_t hi, uint8_t lo)
|
|
{
|
|
if (hi == ctx->prev_cmd[0] && lo == ctx->prev_cmd[1]) {
|
|
/* ignore redundant command */
|
|
} else if ( (hi == 0x10 && (lo >= 0x40 && lo <= 0x5f)) ||
|
|
( (hi >= 0x11 && hi <= 0x17) && (lo >= 0x40 && lo <= 0x7f) ) ) {
|
|
handle_pac(ctx, hi, lo);
|
|
} else if ( ( hi == 0x11 && lo >= 0x20 && lo <= 0x2f ) ||
|
|
( hi == 0x17 && lo >= 0x2e && lo <= 0x2f) ) {
|
|
handle_textattr(ctx, hi, lo);
|
|
} else if (hi == 0x14 || hi == 0x15 || hi == 0x1c) {
|
|
switch (lo) {
|
|
case 0x20:
|
|
/* resume caption loading */
|
|
ctx->mode = CCMODE_POPON;
|
|
break;
|
|
case 0x24:
|
|
handle_delete_end_of_row(ctx, hi, lo);
|
|
break;
|
|
case 0x25:
|
|
case 0x26:
|
|
case 0x27:
|
|
ctx->rollup = lo - 0x23;
|
|
ctx->mode = CCMODE_ROLLUP;
|
|
break;
|
|
case 0x29:
|
|
/* resume direct captioning */
|
|
ctx->mode = CCMODE_PAINTON;
|
|
break;
|
|
case 0x2b:
|
|
/* resume text display */
|
|
ctx->mode = CCMODE_TEXT;
|
|
break;
|
|
case 0x2c:
|
|
/* erase display memory */
|
|
handle_edm(ctx, pts);
|
|
break;
|
|
case 0x2d:
|
|
/* carriage return */
|
|
ff_dlog(ctx, "carriage return\n");
|
|
if (!ctx->real_time)
|
|
reap_screen(ctx, pts);
|
|
roll_up(ctx);
|
|
ctx->cursor_column = 0;
|
|
break;
|
|
case 0x2e:
|
|
/* erase buffered (non displayed) memory */
|
|
// Only in realtime mode. In buffered mode, we re-use the inactive screen
|
|
// for our own buffering.
|
|
if (ctx->real_time) {
|
|
struct Screen *screen = ctx->screen + !ctx->active_screen;
|
|
screen->row_used = 0;
|
|
}
|
|
break;
|
|
case 0x2f:
|
|
/* end of caption */
|
|
ff_dlog(ctx, "handle_eoc\n");
|
|
handle_eoc(ctx, pts);
|
|
break;
|
|
default:
|
|
ff_dlog(ctx, "Unknown command 0x%hhx 0x%hhx\n", hi, lo);
|
|
break;
|
|
}
|
|
} else if (hi >= 0x20) {
|
|
/* Standard characters (always in pairs) */
|
|
handle_char(ctx, hi, lo, pts);
|
|
} else {
|
|
/* Ignoring all other non data code */
|
|
ff_dlog(ctx, "Unknown command 0x%hhx 0x%hhx\n", hi, lo);
|
|
}
|
|
|
|
/* set prev command */
|
|
ctx->prev_cmd[0] = hi;
|
|
ctx->prev_cmd[1] = lo;
|
|
}
|
|
|
|
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
|
|
{
|
|
CCaptionSubContext *ctx = avctx->priv_data;
|
|
AVSubtitle *sub = data;
|
|
uint8_t *bptr = NULL;
|
|
int len = avpkt->size;
|
|
int ret = 0;
|
|
int i;
|
|
|
|
if (ctx->pktbuf->size < len) {
|
|
ret = av_buffer_realloc(&ctx->pktbuf, len);
|
|
if (ret < 0) {
|
|
av_log(ctx, AV_LOG_WARNING, "Insufficient Memory of %d truncated to %d\n", len, ctx->pktbuf->size);
|
|
len = ctx->pktbuf->size;
|
|
ret = 0;
|
|
}
|
|
}
|
|
memcpy(ctx->pktbuf->data, avpkt->data, len);
|
|
bptr = ctx->pktbuf->data;
|
|
|
|
for (i = 0; i < len; i += 3) {
|
|
uint8_t cc_type = *(bptr + i) & 3;
|
|
if (validate_cc_data_pair(bptr + i))
|
|
continue;
|
|
/* ignoring data field 1 */
|
|
if(cc_type == 1)
|
|
continue;
|
|
else
|
|
process_cc608(ctx, avpkt->pts, *(bptr + i + 1) & 0x7f, *(bptr + i + 2) & 0x7f);
|
|
|
|
if (!ctx->buffer_changed)
|
|
continue;
|
|
ctx->buffer_changed = 0;
|
|
|
|
if (*ctx->buffer.str || ctx->real_time)
|
|
{
|
|
int64_t sub_pts = ctx->real_time ? avpkt->pts : ctx->start_time;
|
|
int start_time = av_rescale_q(sub_pts, avctx->time_base, ass_tb);
|
|
int duration = -1;
|
|
if (!ctx->real_time) {
|
|
int end_time = av_rescale_q(ctx->end_time, avctx->time_base, ass_tb);
|
|
duration = end_time - start_time;
|
|
}
|
|
ff_dlog(ctx, "cdp writing data (%s)\n",ctx->buffer.str);
|
|
ret = ff_ass_add_rect_bprint(sub, &ctx->buffer, start_time, duration);
|
|
if (ret < 0)
|
|
return ret;
|
|
sub->pts = av_rescale_q(sub_pts, avctx->time_base, AV_TIME_BASE_Q);
|
|
ctx->buffer_changed = 0;
|
|
ctx->last_real_time = avpkt->pts;
|
|
ctx->screen_touched = 0;
|
|
}
|
|
}
|
|
|
|
if (ctx->real_time && ctx->screen_touched &&
|
|
avpkt->pts > ctx->last_real_time + av_rescale_q(20, ass_tb, avctx->time_base)) {
|
|
int start_time;
|
|
ctx->last_real_time = avpkt->pts;
|
|
ctx->screen_touched = 0;
|
|
|
|
capture_screen(ctx);
|
|
ctx->buffer_changed = 0;
|
|
|
|
start_time = av_rescale_q(avpkt->pts, avctx->time_base, ass_tb);
|
|
ret = ff_ass_add_rect_bprint(sub, &ctx->buffer, start_time, -1);
|
|
if (ret < 0)
|
|
return ret;
|
|
sub->pts = av_rescale_q(avpkt->pts, avctx->time_base, AV_TIME_BASE_Q);
|
|
}
|
|
|
|
*got_sub = sub->num_rects > 0;
|
|
return ret;
|
|
}
|
|
|
|
#define OFFSET(x) offsetof(CCaptionSubContext, x)
|
|
#define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM
|
|
static const AVOption options[] = {
|
|
{ "real_time", "emit subtitle events as they are decoded for real-time display", OFFSET(real_time), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, SD },
|
|
{NULL}
|
|
};
|
|
|
|
static const AVClass ccaption_dec_class = {
|
|
.class_name = "Closed caption Decoder",
|
|
.item_name = av_default_item_name,
|
|
.option = options,
|
|
.version = LIBAVUTIL_VERSION_INT,
|
|
};
|
|
|
|
AVCodec ff_ccaption_decoder = {
|
|
.name = "cc_dec",
|
|
.long_name = NULL_IF_CONFIG_SMALL("Closed Caption (EIA-608 / CEA-708) Decoder"),
|
|
.type = AVMEDIA_TYPE_SUBTITLE,
|
|
.id = AV_CODEC_ID_EIA_608,
|
|
.priv_data_size = sizeof(CCaptionSubContext),
|
|
.init = init_decoder,
|
|
.close = close_decoder,
|
|
.flush = flush_decoder,
|
|
.decode = decode,
|
|
.priv_class = &ccaption_dec_class,
|
|
};
|