| /* |
| * Closed Caption Decoding |
| * Copyright (c) 2015 Anshul Maheshwari |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include "avcodec.h" |
| #include "ass.h" |
| #include "libavutil/opt.h" |
| |
| #define SCREEN_ROWS 15 |
| #define SCREEN_COLUMNS 32 |
| |
| #define SET_FLAG(var, val) ( (var) |= ( 1 << (val)) ) |
| #define UNSET_FLAG(var, val) ( (var) &= ~( 1 << (val)) ) |
| #define CHECK_FLAG(var, val) ( (var) & ( 1 << (val)) ) |
| |
| static const AVRational ms_tb = {1, 1000}; |
| |
| /* |
| * TODO list |
| * 1) handle font and color completely |
| */ |
| enum cc_mode { |
| CCMODE_POPON, |
| CCMODE_PAINTON, |
| CCMODE_ROLLUP, |
| CCMODE_TEXT, |
| }; |
| |
| enum cc_color_code { |
| CCCOL_WHITE, |
| CCCOL_GREEN, |
| CCCOL_BLUE, |
| CCCOL_CYAN, |
| CCCOL_RED, |
| CCCOL_YELLOW, |
| CCCOL_MAGENTA, |
| CCCOL_USERDEFINED, |
| CCCOL_BLACK, |
| CCCOL_TRANSPARENT, |
| }; |
| |
| enum cc_font { |
| CCFONT_REGULAR, |
| CCFONT_ITALICS, |
| CCFONT_UNDERLINED, |
| CCFONT_UNDERLINED_ITALICS, |
| }; |
| |
| enum cc_charset { |
| CCSET_BASIC_AMERICAN, |
| CCSET_SPECIAL_AMERICAN, |
| CCSET_EXTENDED_SPANISH_FRENCH_MISC, |
| CCSET_EXTENDED_PORTUGUESE_GERMAN_DANISH, |
| }; |
| |
| static const char *charset_overrides[4][128] = |
| { |
| [CCSET_BASIC_AMERICAN] = { |
| [0x27] = "\u2019", |
| [0x2a] = "\u00e1", |
| [0x5c] = "\u00e9", |
| [0x5e] = "\u00ed", |
| [0x5f] = "\u00f3", |
| [0x60] = "\u00fa", |
| [0x7b] = "\u00e7", |
| [0x7c] = "\u00f7", |
| [0x7d] = "\u00d1", |
| [0x7e] = "\u00f1", |
| [0x7f] = "\u2588" |
| }, |
| [CCSET_SPECIAL_AMERICAN] = { |
| [0x30] = "\u00ae", |
| [0x31] = "\u00b0", |
| [0x32] = "\u00bd", |
| [0x33] = "\u00bf", |
| [0x34] = "\u2122", |
| [0x35] = "\u00a2", |
| [0x36] = "\u00a3", |
| [0x37] = "\u266a", |
| [0x38] = "\u00e0", |
| [0x39] = "\u00A0", |
| [0x3a] = "\u00e8", |
| [0x3b] = "\u00e2", |
| [0x3c] = "\u00ea", |
| [0x3d] = "\u00ee", |
| [0x3e] = "\u00f4", |
| [0x3f] = "\u00fb", |
| }, |
| [CCSET_EXTENDED_SPANISH_FRENCH_MISC] = { |
| [0x20] = "\u00c1", |
| [0x21] = "\u00c9", |
| [0x22] = "\u00d3", |
| [0x23] = "\u00da", |
| [0x24] = "\u00dc", |
| [0x25] = "\u00fc", |
| [0x26] = "\u00b4", |
| [0x27] = "\u00a1", |
| [0x28] = "*", |
| [0x29] = "\u2018", |
| [0x2a] = "-", |
| [0x2b] = "\u00a9", |
| [0x2c] = "\u2120", |
| [0x2d] = "\u00b7", |
| [0x2e] = "\u201c", |
| [0x2f] = "\u201d", |
| [0x30] = "\u00c0", |
| [0x31] = "\u00c2", |
| [0x32] = "\u00c7", |
| [0x33] = "\u00c8", |
| [0x34] = "\u00ca", |
| [0x35] = "\u00cb", |
| [0x36] = "\u00eb", |
| [0x37] = "\u00ce", |
| [0x38] = "\u00cf", |
| [0x39] = "\u00ef", |
| [0x3a] = "\u00d4", |
| [0x3b] = "\u00d9", |
| [0x3c] = "\u00f9", |
| [0x3d] = "\u00db", |
| [0x3e] = "\u00ab", |
| [0x3f] = "\u00bb", |
| }, |
| [CCSET_EXTENDED_PORTUGUESE_GERMAN_DANISH] = { |
| [0x20] = "\u00c3", |
| [0x21] = "\u00e3", |
| [0x22] = "\u00cd", |
| [0x23] = "\u00cc", |
| [0x24] = "\u00ec", |
| [0x25] = "\u00d2", |
| [0x26] = "\u00f2", |
| [0x27] = "\u00d5", |
| [0x28] = "\u00f5", |
| [0x29] = "{", |
| [0x2a] = "}", |
| [0x2b] = "\\", |
| [0x2c] = "^", |
| [0x2d] = "_", |
| [0x2e] = "|", |
| [0x2f] = "~", |
| [0x30] = "\u00c4", |
| [0x31] = "\u00e4", |
| [0x32] = "\u00d6", |
| [0x33] = "\u00f6", |
| [0x34] = "\u00df", |
| [0x35] = "\u00a5", |
| [0x36] = "\u00a4", |
| [0x37] = "\u00a6", |
| [0x38] = "\u00c5", |
| [0x39] = "\u00e5", |
| [0x3a] = "\u00d8", |
| [0x3b] = "\u00f8", |
| [0x3c] = "\u250c", |
| [0x3d] = "\u2510", |
| [0x3e] = "\u2514", |
| [0x3f] = "\u2518", |
| }, |
| }; |
| |
| static const unsigned char pac2_attribs[32][3] = // Color, font, ident |
| { |
| { CCCOL_WHITE, CCFONT_REGULAR, 0 }, // 0x40 || 0x60 |
| { CCCOL_WHITE, CCFONT_UNDERLINED, 0 }, // 0x41 || 0x61 |
| { CCCOL_GREEN, CCFONT_REGULAR, 0 }, // 0x42 || 0x62 |
| { CCCOL_GREEN, CCFONT_UNDERLINED, 0 }, // 0x43 || 0x63 |
| { CCCOL_BLUE, CCFONT_REGULAR, 0 }, // 0x44 || 0x64 |
| { CCCOL_BLUE, CCFONT_UNDERLINED, 0 }, // 0x45 || 0x65 |
| { CCCOL_CYAN, CCFONT_REGULAR, 0 }, // 0x46 || 0x66 |
| { CCCOL_CYAN, CCFONT_UNDERLINED, 0 }, // 0x47 || 0x67 |
| { CCCOL_RED, CCFONT_REGULAR, 0 }, // 0x48 || 0x68 |
| { CCCOL_RED, CCFONT_UNDERLINED, 0 }, // 0x49 || 0x69 |
| { CCCOL_YELLOW, CCFONT_REGULAR, 0 }, // 0x4a || 0x6a |
| { CCCOL_YELLOW, CCFONT_UNDERLINED, 0 }, // 0x4b || 0x6b |
| { CCCOL_MAGENTA, CCFONT_REGULAR, 0 }, // 0x4c || 0x6c |
| { CCCOL_MAGENTA, CCFONT_UNDERLINED, 0 }, // 0x4d || 0x6d |
| { CCCOL_WHITE, CCFONT_ITALICS, 0 }, // 0x4e || 0x6e |
| { CCCOL_WHITE, CCFONT_UNDERLINED_ITALICS, 0 }, // 0x4f || 0x6f |
| { CCCOL_WHITE, CCFONT_REGULAR, 0 }, // 0x50 || 0x70 |
| { CCCOL_WHITE, CCFONT_UNDERLINED, 0 }, // 0x51 || 0x71 |
| { CCCOL_WHITE, CCFONT_REGULAR, 4 }, // 0x52 || 0x72 |
| { CCCOL_WHITE, CCFONT_UNDERLINED, 4 }, // 0x53 || 0x73 |
| { CCCOL_WHITE, CCFONT_REGULAR, 8 }, // 0x54 || 0x74 |
| { CCCOL_WHITE, CCFONT_UNDERLINED, 8 }, // 0x55 || 0x75 |
| { CCCOL_WHITE, CCFONT_REGULAR, 12 }, // 0x56 || 0x76 |
| { CCCOL_WHITE, CCFONT_UNDERLINED, 12 }, // 0x57 || 0x77 |
| { CCCOL_WHITE, CCFONT_REGULAR, 16 }, // 0x58 || 0x78 |
| { CCCOL_WHITE, CCFONT_UNDERLINED, 16 }, // 0x59 || 0x79 |
| { CCCOL_WHITE, CCFONT_REGULAR, 20 }, // 0x5a || 0x7a |
| { CCCOL_WHITE, CCFONT_UNDERLINED, 20 }, // 0x5b || 0x7b |
| { CCCOL_WHITE, CCFONT_REGULAR, 24 }, // 0x5c || 0x7c |
| { CCCOL_WHITE, CCFONT_UNDERLINED, 24 }, // 0x5d || 0x7d |
| { CCCOL_WHITE, CCFONT_REGULAR, 28 }, // 0x5e || 0x7e |
| { CCCOL_WHITE, CCFONT_UNDERLINED, 28 } // 0x5f || 0x7f |
| /* total 32 entries */ |
| }; |
| |
| struct Screen { |
| /* +1 is used to compensate null character of string */ |
| uint8_t characters[SCREEN_ROWS+1][SCREEN_COLUMNS+1]; |
| uint8_t charsets[SCREEN_ROWS+1][SCREEN_COLUMNS+1]; |
| uint8_t colors[SCREEN_ROWS+1][SCREEN_COLUMNS+1]; |
| uint8_t fonts[SCREEN_ROWS+1][SCREEN_COLUMNS+1]; |
| /* |
| * Bitmask of used rows; if a bit is not set, the |
| * corresponding row is not used. |
| * for setting row 1 use row | (1 << 0) |
| * for setting row 15 use row | (1 << 14) |
| */ |
| int16_t row_used; |
| }; |
| |
| typedef struct CCaptionSubContext { |
| AVClass *class; |
| int real_time; |
| struct Screen screen[2]; |
| int active_screen; |
| uint8_t cursor_row; |
| uint8_t cursor_column; |
| uint8_t cursor_color; |
| uint8_t cursor_font; |
| uint8_t cursor_charset; |
| AVBPrint buffer; |
| int buffer_changed; |
| int rollup; |
| enum cc_mode mode; |
| int64_t start_time; |
| /* visible screen time */ |
| int64_t startv_time; |
| int64_t end_time; |
| int screen_touched; |
| int64_t last_real_time; |
| char prev_cmd[2]; |
| /* buffer to store pkt data */ |
| uint8_t *pktbuf; |
| int pktbuf_size; |
| int readorder; |
| } CCaptionSubContext; |
| |
| |
| static av_cold int init_decoder(AVCodecContext *avctx) |
| { |
| int ret; |
| CCaptionSubContext *ctx = avctx->priv_data; |
| |
| av_bprint_init(&ctx->buffer, 0, AV_BPRINT_SIZE_UNLIMITED); |
| /* taking by default roll up to 2 */ |
| ctx->mode = CCMODE_ROLLUP; |
| ctx->rollup = 2; |
| ctx->cursor_row = 10; |
| ret = ff_ass_subtitle_header(avctx, "Monospace", |
| ASS_DEFAULT_FONT_SIZE, |
| ASS_DEFAULT_COLOR, |
| ASS_DEFAULT_BACK_COLOR, |
| ASS_DEFAULT_BOLD, |
| ASS_DEFAULT_ITALIC, |
| ASS_DEFAULT_UNDERLINE, |
| 3, |
| ASS_DEFAULT_ALIGNMENT); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| return ret; |
| } |
| |
| static av_cold int close_decoder(AVCodecContext *avctx) |
| { |
| CCaptionSubContext *ctx = avctx->priv_data; |
| av_bprint_finalize(&ctx->buffer, NULL); |
| av_freep(&ctx->pktbuf); |
| ctx->pktbuf_size = 0; |
| return 0; |
| } |
| |
| static void flush_decoder(AVCodecContext *avctx) |
| { |
| CCaptionSubContext *ctx = avctx->priv_data; |
| ctx->screen[0].row_used = 0; |
| ctx->screen[1].row_used = 0; |
| ctx->prev_cmd[0] = 0; |
| ctx->prev_cmd[1] = 0; |
| ctx->mode = CCMODE_ROLLUP; |
| ctx->rollup = 2; |
| ctx->cursor_row = 10; |
| ctx->cursor_column = 0; |
| ctx->cursor_font = 0; |
| ctx->cursor_color = 0; |
| ctx->cursor_charset = 0; |
| ctx->active_screen = 0; |
| ctx->last_real_time = 0; |
| ctx->screen_touched = 0; |
| ctx->buffer_changed = 0; |
| if (!(avctx->flags2 & AV_CODEC_FLAG2_RO_FLUSH_NOOP)) |
| ctx->readorder = 0; |
| av_bprint_clear(&ctx->buffer); |
| } |
| |
| /** |
| * @param ctx closed caption context just to print log |
| */ |
| static void write_char(CCaptionSubContext *ctx, struct Screen *screen, char ch) |
| { |
| uint8_t col = ctx->cursor_column; |
| char *row = screen->characters[ctx->cursor_row]; |
| char *font = screen->fonts[ctx->cursor_row]; |
| char *charset = screen->charsets[ctx->cursor_row]; |
| |
| if (col < SCREEN_COLUMNS) { |
| row[col] = ch; |
| font[col] = ctx->cursor_font; |
| charset[col] = ctx->cursor_charset; |
| ctx->cursor_charset = CCSET_BASIC_AMERICAN; |
| if (ch) ctx->cursor_column++; |
| return; |
| } |
| /* We have extra space at end only for null character */ |
| else if (col == SCREEN_COLUMNS && ch == 0) { |
| row[col] = ch; |
| return; |
| } |
| else { |
| av_log(ctx, AV_LOG_WARNING, "Data Ignored since exceeding screen width\n"); |
| return; |
| } |
| } |
| |
| /** |
| * This function after validating parity bit, also remove it from data pair. |
| * The first byte doesn't pass parity, we replace it with a solid blank |
| * and process the pair. |
| * If the second byte doesn't pass parity, it returns INVALIDDATA |
| * user can ignore the whole pair and pass the other pair. |
| */ |
| static int validate_cc_data_pair(uint8_t *cc_data_pair) |
| { |
| uint8_t cc_valid = (*cc_data_pair & 4) >>2; |
| uint8_t cc_type = *cc_data_pair & 3; |
| |
| if (!cc_valid) |
| return AVERROR_INVALIDDATA; |
| |
| // if EIA-608 data then verify parity. |
| if (cc_type==0 || cc_type==1) { |
| if (!av_parity(cc_data_pair[2])) { |
| return AVERROR_INVALIDDATA; |
| } |
| if (!av_parity(cc_data_pair[1])) { |
| cc_data_pair[1]=0x7F; |
| } |
| } |
| |
| //Skip non-data |
| if ((cc_data_pair[0] == 0xFA || cc_data_pair[0] == 0xFC || cc_data_pair[0] == 0xFD) |
| && (cc_data_pair[1] & 0x7F) == 0 && (cc_data_pair[2] & 0x7F) == 0) |
| return AVERROR_PATCHWELCOME; |
| |
| //skip 708 data |
| if (cc_type == 3 || cc_type == 2) |
| return AVERROR_PATCHWELCOME; |
| |
| /* remove parity bit */ |
| cc_data_pair[1] &= 0x7F; |
| cc_data_pair[2] &= 0x7F; |
| |
| return 0; |
| } |
| |
| static struct Screen *get_writing_screen(CCaptionSubContext *ctx) |
| { |
| switch (ctx->mode) { |
| case CCMODE_POPON: |
| // use Inactive screen |
| return ctx->screen + !ctx->active_screen; |
| case CCMODE_PAINTON: |
| case CCMODE_ROLLUP: |
| case CCMODE_TEXT: |
| // use active screen |
| return ctx->screen + ctx->active_screen; |
| } |
| /* It was never an option */ |
| return NULL; |
| } |
| |
| static void roll_up(CCaptionSubContext *ctx) |
| { |
| struct Screen *screen; |
| int i, keep_lines; |
| |
| if (ctx->mode == CCMODE_TEXT) |
| return; |
| |
| screen = get_writing_screen(ctx); |
| |
| /* +1 signify cursor_row starts from 0 |
| * Can't keep lines less then row cursor pos |
| */ |
| keep_lines = FFMIN(ctx->cursor_row + 1, ctx->rollup); |
| |
| for (i = 0; i < SCREEN_ROWS; i++) { |
| if (i > ctx->cursor_row - keep_lines && i <= ctx->cursor_row) |
| continue; |
| UNSET_FLAG(screen->row_used, i); |
| } |
| |
| for (i = 0; i < keep_lines && screen->row_used; i++) { |
| const int i_row = ctx->cursor_row - keep_lines + i + 1; |
| |
| memcpy(screen->characters[i_row], screen->characters[i_row+1], SCREEN_COLUMNS); |
| memcpy(screen->colors[i_row], screen->colors[i_row+1], SCREEN_COLUMNS); |
| memcpy(screen->fonts[i_row], screen->fonts[i_row+1], SCREEN_COLUMNS); |
| memcpy(screen->charsets[i_row], screen->charsets[i_row+1], SCREEN_COLUMNS); |
| if (CHECK_FLAG(screen->row_used, i_row + 1)) |
| SET_FLAG(screen->row_used, i_row); |
| } |
| |
| UNSET_FLAG(screen->row_used, ctx->cursor_row); |
| } |
| |
| static int capture_screen(CCaptionSubContext *ctx) |
| { |
| int i, j, tab = 0; |
| struct Screen *screen = ctx->screen + ctx->active_screen; |
| enum cc_font prev_font = CCFONT_REGULAR; |
| av_bprint_clear(&ctx->buffer); |
| |
| for (i = 0; screen->row_used && i < SCREEN_ROWS; i++) |
| { |
| if (CHECK_FLAG(screen->row_used, i)) { |
| const char *row = screen->characters[i]; |
| const char *charset = screen->charsets[i]; |
| j = 0; |
| while (row[j] == ' ' && charset[j] == CCSET_BASIC_AMERICAN) |
| j++; |
| if (!tab || j < tab) |
| tab = j; |
| } |
| } |
| |
| for (i = 0; screen->row_used && i < SCREEN_ROWS; i++) |
| { |
| if (CHECK_FLAG(screen->row_used, i)) { |
| const char *row = screen->characters[i]; |
| const char *font = screen->fonts[i]; |
| const char *charset = screen->charsets[i]; |
| const char *override; |
| int x, y, seen_char = 0; |
| j = 0; |
| |
| /* skip leading space */ |
| while (row[j] == ' ' && charset[j] == CCSET_BASIC_AMERICAN && j < tab) |
| j++; |
| |
| x = ASS_DEFAULT_PLAYRESX * (0.1 + 0.0250 * j); |
| y = ASS_DEFAULT_PLAYRESY * (0.1 + 0.0533 * i); |
| av_bprintf(&ctx->buffer, "{\\an7}{\\pos(%d,%d)}", x, y); |
| |
| for (; j < SCREEN_COLUMNS; j++) { |
| const char *e_tag = "", *s_tag = ""; |
| |
| if (row[j] == 0) |
| break; |
| |
| if (prev_font != font[j]) { |
| switch (prev_font) { |
| case CCFONT_ITALICS: |
| e_tag = "{\\i0}"; |
| break; |
| case CCFONT_UNDERLINED: |
| e_tag = "{\\u0}"; |
| break; |
| case CCFONT_UNDERLINED_ITALICS: |
| e_tag = "{\\u0}{\\i0}"; |
| break; |
| } |
| switch (font[j]) { |
| case CCFONT_ITALICS: |
| s_tag = "{\\i1}"; |
| break; |
| case CCFONT_UNDERLINED: |
| s_tag = "{\\u1}"; |
| break; |
| case CCFONT_UNDERLINED_ITALICS: |
| s_tag = "{\\u1}{\\i1}"; |
| break; |
| } |
| } |
| prev_font = font[j]; |
| override = charset_overrides[(int)charset[j]][(int)row[j]]; |
| if (override) { |
| av_bprintf(&ctx->buffer, "%s%s%s", e_tag, s_tag, override); |
| seen_char = 1; |
| } else if (row[j] == ' ' && !seen_char) { |
| av_bprintf(&ctx->buffer, "%s%s\\h", e_tag, s_tag); |
| } else { |
| av_bprintf(&ctx->buffer, "%s%s%c", e_tag, s_tag, row[j]); |
| seen_char = 1; |
| } |
| |
| } |
| av_bprintf(&ctx->buffer, "\\N"); |
| } |
| } |
| if (!av_bprint_is_complete(&ctx->buffer)) |
| return AVERROR(ENOMEM); |
| if (screen->row_used && ctx->buffer.len >= 2) { |
| ctx->buffer.len -= 2; |
| ctx->buffer.str[ctx->buffer.len] = 0; |
| } |
| ctx->buffer_changed = 1; |
| return 0; |
| } |
| |
| static int reap_screen(CCaptionSubContext *ctx, int64_t pts) |
| { |
| ctx->start_time = ctx->startv_time; |
| ctx->startv_time = pts; |
| ctx->end_time = pts; |
| return capture_screen(ctx); |
| } |
| |
| static void handle_textattr(CCaptionSubContext *ctx, uint8_t hi, uint8_t lo) |
| { |
| int i = lo - 0x20; |
| struct Screen *screen = get_writing_screen(ctx); |
| |
| if (i >= 32) |
| return; |
| |
| ctx->cursor_color = pac2_attribs[i][0]; |
| ctx->cursor_font = pac2_attribs[i][1]; |
| |
| SET_FLAG(screen->row_used, ctx->cursor_row); |
| write_char(ctx, screen, ' '); |
| } |
| |
| static void handle_pac(CCaptionSubContext *ctx, uint8_t hi, uint8_t lo) |
| { |
| static const int8_t row_map[] = { |
| 11, -1, 1, 2, 3, 4, 12, 13, 14, 15, 5, 6, 7, 8, 9, 10 |
| }; |
| const int index = ( (hi<<1) & 0x0e) | ( (lo>>5) & 0x01 ); |
| struct Screen *screen = get_writing_screen(ctx); |
| int indent, i; |
| |
| if (row_map[index] <= 0) { |
| av_log(ctx, AV_LOG_DEBUG, "Invalid pac index encountered\n"); |
| return; |
| } |
| |
| lo &= 0x1f; |
| |
| ctx->cursor_row = row_map[index] - 1; |
| ctx->cursor_color = pac2_attribs[lo][0]; |
| ctx->cursor_font = pac2_attribs[lo][1]; |
| ctx->cursor_charset = CCSET_BASIC_AMERICAN; |
| ctx->cursor_column = 0; |
| indent = pac2_attribs[lo][2]; |
| for (i = 0; i < indent; i++) { |
| write_char(ctx, screen, ' '); |
| } |
| } |
| |
| /** |
| * @param pts it is required to set end time |
| */ |
| static void handle_edm(CCaptionSubContext *ctx, int64_t pts) |
| { |
| struct Screen *screen = ctx->screen + ctx->active_screen; |
| |
| // In buffered mode, keep writing to screen until it is wiped. |
| // Before wiping the display, capture contents to emit subtitle. |
| if (!ctx->real_time) |
| reap_screen(ctx, pts); |
| |
| screen->row_used = 0; |
| |
| // In realtime mode, emit an empty caption so the last one doesn't |
| // stay on the screen. |
| if (ctx->real_time) |
| reap_screen(ctx, pts); |
| } |
| |
| static void handle_eoc(CCaptionSubContext *ctx, int64_t pts) |
| { |
| // In buffered mode, we wait til the *next* EOC and |
| // reap what was already on the screen since the last EOC. |
| if (!ctx->real_time) |
| handle_edm(ctx,pts); |
| |
| ctx->active_screen = !ctx->active_screen; |
| ctx->cursor_column = 0; |
| |
| // In realtime mode, we display the buffered contents (after |
| // flipping the buffer to active above) as soon as EOC arrives. |
| if (ctx->real_time) |
| reap_screen(ctx, pts); |
| } |
| |
| static void handle_delete_end_of_row(CCaptionSubContext *ctx, char hi, char lo) |
| { |
| struct Screen *screen = get_writing_screen(ctx); |
| write_char(ctx, screen, 0); |
| } |
| |
| static void handle_char(CCaptionSubContext *ctx, char hi, char lo, int64_t pts) |
| { |
| struct Screen *screen = get_writing_screen(ctx); |
| |
| SET_FLAG(screen->row_used, ctx->cursor_row); |
| |
| switch (hi) { |
| case 0x11: |
| ctx->cursor_charset = CCSET_SPECIAL_AMERICAN; |
| break; |
| case 0x12: |
| if (ctx->cursor_column > 0) |
| ctx->cursor_column -= 1; |
| ctx->cursor_charset = CCSET_EXTENDED_SPANISH_FRENCH_MISC; |
| break; |
| case 0x13: |
| if (ctx->cursor_column > 0) |
| ctx->cursor_column -= 1; |
| ctx->cursor_charset = CCSET_EXTENDED_PORTUGUESE_GERMAN_DANISH; |
| break; |
| default: |
| ctx->cursor_charset = CCSET_BASIC_AMERICAN; |
| write_char(ctx, screen, hi); |
| break; |
| } |
| |
| if (lo) { |
| write_char(ctx, screen, lo); |
| } |
| write_char(ctx, screen, 0); |
| |
| if (ctx->mode != CCMODE_POPON) |
| ctx->screen_touched = 1; |
| |
| 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 */ |
| return; |
| } |
| |
| /* set prev command */ |
| ctx->prev_cmd[0] = hi; |
| ctx->prev_cmd[1] = lo; |
| |
| 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 >= 0x11 && hi <= 0x13) { |
| /* Special characters */ |
| handle_char(ctx, hi, lo, pts); |
| } else if (hi >= 0x20) { |
| /* Standard characters (always in pairs) */ |
| handle_char(ctx, hi, lo, pts); |
| ctx->prev_cmd[0] = ctx->prev_cmd[1] = 0; |
| } else if (hi == 0x17 && lo >= 0x21 && lo <= 0x23) { |
| int i; |
| /* Tab offsets (spacing) */ |
| for (i = 0; i < lo - 0x20; i++) { |
| handle_char(ctx, ' ', 0, pts); |
| } |
| } else { |
| /* Ignoring all other non data code */ |
| ff_dlog(ctx, "Unknown command 0x%hhx 0x%hhx\n", hi, lo); |
| } |
| } |
| |
| static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt) |
| { |
| CCaptionSubContext *ctx = avctx->priv_data; |
| AVSubtitle *sub = data; |
| const int64_t start_time = sub->pts; |
| uint8_t *bptr = NULL; |
| int len = avpkt->size; |
| int ret = 0; |
| int i; |
| |
| av_fast_padded_malloc(&ctx->pktbuf, &ctx->pktbuf_size, len); |
| if (!ctx->pktbuf) { |
| av_log(ctx, AV_LOG_WARNING, "Insufficient Memory of %d truncated to %d\n", len, ctx->pktbuf_size); |
| return AVERROR(ENOMEM); |
| } |
| memcpy(ctx->pktbuf, avpkt->data, len); |
| bptr = ctx->pktbuf; |
| |
| 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, start_time, *(bptr + i + 1) & 0x7f, *(bptr + i + 2) & 0x7f); |
| |
| if (!ctx->buffer_changed) |
| continue; |
| ctx->buffer_changed = 0; |
| |
| if (*ctx->buffer.str || ctx->real_time) |
| { |
| ff_dlog(ctx, "cdp writing data (%s)\n",ctx->buffer.str); |
| ret = ff_ass_add_rect(sub, ctx->buffer.str, ctx->readorder++, 0, NULL, NULL); |
| if (ret < 0) |
| return ret; |
| sub->pts = ctx->start_time; |
| if (!ctx->real_time) |
| sub->end_display_time = av_rescale_q(ctx->end_time - ctx->start_time, |
| AV_TIME_BASE_Q, ms_tb); |
| else |
| sub->end_display_time = -1; |
| ctx->buffer_changed = 0; |
| ctx->last_real_time = sub->pts; |
| ctx->screen_touched = 0; |
| } |
| } |
| |
| if (ctx->real_time && ctx->screen_touched && |
| sub->pts > ctx->last_real_time + av_rescale_q(200, ms_tb, AV_TIME_BASE_Q)) { |
| ctx->last_real_time = sub->pts; |
| ctx->screen_touched = 0; |
| |
| capture_screen(ctx); |
| ctx->buffer_changed = 0; |
| |
| ret = ff_ass_add_rect(sub, ctx->buffer.str, ctx->readorder++, 0, NULL, NULL); |
| if (ret < 0) |
| return ret; |
| sub->end_display_time = -1; |
| } |
| |
| *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)"), |
| .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, |
| }; |
