| /* | |
| * Teletext decoding for ffmpeg | |
| * Copyright (c) 2005-2010, 2012 Wolfram Gloger | |
| * Copyright (c) 2013 Marton Balint | |
| * | |
| * This library 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 of the License, or (at your option) any later version. | |
| * | |
| * This library 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 this library; if not, write to the Free Software | |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| */ | |
| #include "avcodec.h" | |
| #include "libavcodec/ass.h" | |
| #include "codec_internal.h" | |
| #include "libavcodec/dvbtxt.h" | |
| #include "libavutil/opt.h" | |
| #include "libavutil/bprint.h" | |
| #include "libavutil/internal.h" | |
| #include "libavutil/intreadwrite.h" | |
| #include "libavutil/log.h" | |
| #include "libavutil/common.h" | |
| #include <libzvbi.h> | |
| #define TEXT_MAXSZ (25 * (56 + 1) * 4 + 2) | |
| #define VBI_NB_COLORS 40 | |
| #define VBI_TRANSPARENT_BLACK 8 | |
| #define RGBA(r,g,b,a) (((a) << 24) | ((r) << 16) | ((g) << 8) | (b)) | |
| #define VBI_R(rgba) (((rgba) >> 0) & 0xFF) | |
| #define VBI_G(rgba) (((rgba) >> 8) & 0xFF) | |
| #define VBI_B(rgba) (((rgba) >> 16) & 0xFF) | |
| #define VBI_A(rgba) (((rgba) >> 24) & 0xFF) | |
| #define MAX_BUFFERED_PAGES 25 | |
| #define BITMAP_CHAR_WIDTH 12 | |
| #define BITMAP_CHAR_HEIGHT 10 | |
| #define MAX_SLICES 64 | |
| typedef struct TeletextPage | |
| { | |
| AVSubtitleRect *sub_rect; | |
| int pgno; | |
| int subno; | |
| int64_t pts; | |
| } TeletextPage; | |
| typedef struct TeletextContext | |
| { | |
| AVClass *class; | |
| char *pgno; | |
| int default_region; | |
| int x_offset; | |
| int y_offset; | |
| int format_id; /* 0 = bitmap, 1 = text/ass, 2 = ass */ | |
| int chop_top; | |
| int sub_duration; /* in msec */ | |
| int transparent_bg; | |
| int opacity; | |
| int chop_spaces; | |
| int lines_processed; | |
| TeletextPage *pages; | |
| int nb_pages; | |
| int64_t pts; | |
| int handler_ret; | |
| vbi_decoder * vbi; | |
| vbi_sliced sliced[MAX_SLICES]; | |
| int readorder; | |
| uint8_t subtitle_map[2048]; | |
| int last_pgno; | |
| int last_p5; | |
| int last_ass_alignment; | |
| } TeletextContext; | |
| static int my_ass_subtitle_header(AVCodecContext *avctx) | |
| { | |
| int ret = ff_ass_subtitle_header_default(avctx); | |
| char *new_header; | |
| uint8_t *event_pos; | |
| if (ret < 0) | |
| return ret; | |
| event_pos = strstr(avctx->subtitle_header, "\r\n[Events]\r\n"); | |
| if (!event_pos) | |
| return AVERROR_BUG; | |
| new_header = av_asprintf("%.*s%s%s", | |
| (int)(event_pos - avctx->subtitle_header), avctx->subtitle_header, | |
| "Style: " | |
| "Teletext," /* Name */ | |
| "Monospace,11," /* Font{name,size} */ | |
| "&Hffffff,&Hffffff,&H0,&H0," /* {Primary,Secondary,Outline,Back}Colour */ | |
| "0,0,0,0," /* Bold, Italic, Underline, StrikeOut */ | |
| "160,100," /* Scale{X,Y} */ | |
| "0,0," /* Spacing, Angle */ | |
| "3,0.1,0," /* BorderStyle, Outline, Shadow */ | |
| "5,1,1,1," /* Alignment, Margin[LRV] */ | |
| "0\r\n" /* Encoding */ | |
| "Style: " | |
| "Subtitle," /* Name */ | |
| "Monospace,16," /* Font{name,size} */ | |
| "&Hffffff,&Hffffff,&H0,&H0," /* {Primary,Secondary,Outline,Back}Colour */ | |
| "0,0,0,0," /* Bold, Italic, Underline, StrikeOut */ | |
| "100,100," /* Scale{X,Y} */ | |
| "0,0," /* Spacing, Angle */ | |
| "1,1,1," /* BorderStyle, Outline, Shadow */ | |
| "8,48,48,20," /* Alignment, Margin[LRV] */ | |
| "0\r\n" /* Encoding */ | |
| , event_pos); | |
| if (!new_header) | |
| return AVERROR(ENOMEM); | |
| av_free(avctx->subtitle_header); | |
| avctx->subtitle_header = new_header; | |
| avctx->subtitle_header_size = strlen(new_header); | |
| return 0; | |
| } | |
| static int chop_spaces_utf8(const unsigned char* t, int len) | |
| { | |
| t += len; | |
| while (len > 0) { | |
| if (*--t != ' ' || (len-1 > 0 && *(t-1) & 0x80)) | |
| break; | |
| --len; | |
| } | |
| return len; | |
| } | |
| static void subtitle_rect_free(AVSubtitleRect **sub_rect) | |
| { | |
| av_freep(&(*sub_rect)->data[0]); | |
| av_freep(&(*sub_rect)->data[1]); | |
| av_freep(&(*sub_rect)->ass); | |
| av_freep(sub_rect); | |
| } | |
| static char *create_ass_text(TeletextContext *ctx, const char *text) | |
| { | |
| char *dialog; | |
| AVBPrint buf; | |
| av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED); | |
| ff_ass_bprint_text_event(&buf, text, strlen(text), "", 0); | |
| if (!av_bprint_is_complete(&buf)) { | |
| av_bprint_finalize(&buf, NULL); | |
| return NULL; | |
| } | |
| dialog = ff_ass_get_dialog(ctx->readorder++, 0, NULL, NULL, buf.str); | |
| av_bprint_finalize(&buf, NULL); | |
| return dialog; | |
| } | |
| /* Draw a page as text */ | |
| static int gen_sub_text(TeletextContext *ctx, AVSubtitleRect *sub_rect, vbi_page *page, int chop_top) | |
| { | |
| const char *in; | |
| AVBPrint buf; | |
| char *vbi_text = av_malloc(TEXT_MAXSZ); | |
| int sz; | |
| if (!vbi_text) | |
| return AVERROR(ENOMEM); | |
| sz = vbi_print_page_region(page, vbi_text, TEXT_MAXSZ-1, "UTF-8", | |
| /*table mode*/ TRUE, FALSE, | |
| 0, chop_top, | |
| page->columns, page->rows-chop_top); | |
| if (sz <= 0) { | |
| av_log(ctx, AV_LOG_ERROR, "vbi_print error\n"); | |
| av_free(vbi_text); | |
| return AVERROR_EXTERNAL; | |
| } | |
| vbi_text[sz] = '\0'; | |
| in = vbi_text; | |
| av_bprint_init(&buf, 0, TEXT_MAXSZ); | |
| if (ctx->chop_spaces) { | |
| for (;;) { | |
| int nl, sz; | |
| // skip leading spaces and newlines | |
| in += strspn(in, " \n"); | |
| // compute end of row | |
| for (nl = 0; in[nl]; ++nl) | |
| if (in[nl] == '\n' && (nl==0 || !(in[nl-1] & 0x80))) | |
| break; | |
| if (!in[nl]) | |
| break; | |
| // skip trailing spaces | |
| sz = chop_spaces_utf8(in, nl); | |
| av_bprint_append_data(&buf, in, sz); | |
| av_bprintf(&buf, "\n"); | |
| in += nl; | |
| } | |
| } else { | |
| av_bprintf(&buf, "%s\n", vbi_text); | |
| } | |
| av_free(vbi_text); | |
| if (!av_bprint_is_complete(&buf)) { | |
| av_bprint_finalize(&buf, NULL); | |
| return AVERROR(ENOMEM); | |
| } | |
| if (buf.len) { | |
| sub_rect->type = SUBTITLE_ASS; | |
| sub_rect->ass = create_ass_text(ctx, buf.str); | |
| if (!sub_rect->ass) { | |
| av_bprint_finalize(&buf, NULL); | |
| return AVERROR(ENOMEM); | |
| } | |
| av_log(ctx, AV_LOG_DEBUG, "subtext:%s:txetbus\n", sub_rect->ass); | |
| } else { | |
| sub_rect->type = SUBTITLE_NONE; | |
| } | |
| av_bprint_finalize(&buf, NULL); | |
| return 0; | |
| } | |
| static void bprint_color(const char *type, AVBPrint *buf, vbi_page *page, unsigned ci) | |
| { | |
| int r = VBI_R(page->color_map[ci]); | |
| int g = VBI_G(page->color_map[ci]); | |
| int b = VBI_B(page->color_map[ci]); | |
| av_bprintf(buf, "{\\%s&H%02X%02X%02X&}", type, b, g, r); | |
| } | |
| #define IS_TXT_SPACE(ch) ((ch).unicode < 0x0020 || (ch).unicode >= 0xe000 || (ch).unicode == 0x00a0 ||\ | |
| (ch).size > VBI_DOUBLE_SIZE || (ch).opacity == VBI_TRANSPARENT_SPACE) | |
| static void get_trim_info(vbi_page *page, vbi_char *row, int *leading, int *trailing, int *olen) | |
| { | |
| int i, len = 0; | |
| int char_seen = 0; | |
| *leading = 0; | |
| for (i = 0; i < page->columns; i++) { | |
| uint16_t out = IS_TXT_SPACE(row[i]) ? 32 : row[i].unicode; | |
| if (out == 32 && !char_seen) | |
| (*leading)++; | |
| else if (out != 32) | |
| char_seen = 1, len = i - (*leading) + 1; | |
| } | |
| *olen = len; | |
| *trailing = len > 0 ? page->columns - *leading - len : page->columns; | |
| } | |
| static void decode_string(vbi_page *page, vbi_char *row, AVBPrint *buf, | |
| int start, int end, vbi_color *cur_color, vbi_color *cur_back_color) | |
| { | |
| int i; | |
| for (i = start; i < end; i++) { | |
| uint16_t out = IS_TXT_SPACE(row[i]) ? 32 : row[i].unicode; | |
| if (*cur_color != row[i].foreground) { | |
| bprint_color("c", buf, page, row[i].foreground); | |
| *cur_color = row[i].foreground; | |
| } | |
| if (*cur_back_color != row[i].background) { | |
| bprint_color("3c", buf, page, row[i].background); | |
| *cur_back_color = row[i].background; | |
| } | |
| if (out == 32) { | |
| av_bprintf(buf, "\\h"); | |
| } else if (out == '\\' || out == '{' || out == '}') { | |
| av_bprintf(buf, "\\%c", (char)out); | |
| } else { | |
| char tmp; | |
| /* convert to utf-8 */ | |
| PUT_UTF8(out, tmp, av_bprint_chars(buf, tmp, 1);); | |
| } | |
| } | |
| } | |
| /* Draw a page as ass formatted text */ | |
| static int gen_sub_ass(TeletextContext *ctx, AVSubtitleRect *sub_rect, vbi_page *page, int chop_top) | |
| { | |
| int i; | |
| int leading, trailing, len; | |
| int last_trailing = -1, last_leading = -1; | |
| int min_trailing = page->columns, min_leading = page->columns; | |
| int alignment = 2; | |
| int vertical_align = -1; | |
| int can_align_left = 1, can_align_right = 1, can_align_center = 1; | |
| int is_subtitle_page = ctx->subtitle_map[page->pgno & 0x7ff]; | |
| int empty_lines = 0; | |
| vbi_color cur_color = VBI_WHITE; | |
| vbi_color cur_back_color = VBI_BLACK; | |
| AVBPrint buf; | |
| av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED); | |
| for (i = chop_top; i < page->rows; i++) { | |
| vbi_char *row = page->text + i * page->columns; | |
| get_trim_info(page, row, &leading, &trailing, &len); | |
| if (len) { | |
| if (last_leading != -1 && last_leading != leading || leading > 5) | |
| can_align_left = 0; | |
| if (last_trailing != -1 && last_trailing != trailing || trailing > 2) | |
| can_align_right = 0; | |
| if (last_trailing != -1 && (FFABS((trailing - leading) - (last_trailing - last_leading)) > 1) || trailing - leading > 4) | |
| can_align_center = 0; | |
| last_leading = leading; | |
| last_trailing = trailing; | |
| min_leading = FFMIN(leading, min_leading); | |
| min_trailing = FFMIN(trailing, min_trailing); | |
| } | |
| } | |
| if (!can_align_right && can_align_left && !can_align_center) { | |
| ctx->last_ass_alignment = alignment = 1; | |
| } else if (!can_align_right && !can_align_left && can_align_center) { | |
| ctx->last_ass_alignment = alignment = 2; | |
| } else if (can_align_right && !can_align_left && !can_align_center) { | |
| ctx->last_ass_alignment = alignment = 3; | |
| } else { | |
| if (ctx->last_ass_alignment == 1 && can_align_left || | |
| ctx->last_ass_alignment == 2 && can_align_center || | |
| ctx->last_ass_alignment == 3 && can_align_right) | |
| alignment = ctx->last_ass_alignment; | |
| } | |
| for (i = chop_top; i < page->rows; i++) { | |
| int j; | |
| vbi_char *row = page->text + i * page->columns; | |
| int is_transparent_line; | |
| for (j = 0; j < page->columns; j++) | |
| if (row[j].opacity != VBI_TRANSPARENT_SPACE) | |
| break; | |
| is_transparent_line = (j == page->columns); | |
| len = is_transparent_line ? 0 : page->columns; | |
| leading = trailing = is_transparent_line ? page->columns : 0; | |
| if (is_subtitle_page) { | |
| if (!is_transparent_line) | |
| get_trim_info(page, row, &leading, &trailing, &len); | |
| if (vertical_align == -1 && len) { | |
| vertical_align = (2 - (av_clip(i + 1, 0, 23) / 8)); | |
| av_bprintf(&buf, "{\\an%d}", alignment + vertical_align * 3); | |
| if (vertical_align != 2) | |
| empty_lines = 0; | |
| } | |
| if (len && empty_lines > 1) | |
| for (empty_lines /= 2; empty_lines > 0; empty_lines--) | |
| av_bprintf(&buf, " \\N"); | |
| if (alignment == 1 || alignment == 2 && !can_align_center) | |
| leading = min_leading; | |
| if (alignment == 3 || alignment == 2 && !can_align_center) | |
| trailing = min_trailing; | |
| } | |
| if (len || !is_subtitle_page) { | |
| decode_string(page, row, &buf, leading, page->columns - trailing, &cur_color, &cur_back_color); | |
| av_bprintf(&buf, " \\N"); | |
| empty_lines = 0; | |
| } else { | |
| empty_lines++; | |
| } | |
| } | |
| if (vertical_align == 0) | |
| for (empty_lines = (empty_lines - 1) / 2; empty_lines > 0; empty_lines--) | |
| av_bprintf(&buf, " \\N"); | |
| if (!av_bprint_is_complete(&buf)) { | |
| av_bprint_finalize(&buf, NULL); | |
| return AVERROR(ENOMEM); | |
| } | |
| if (buf.len) { | |
| sub_rect->type = SUBTITLE_ASS; | |
| sub_rect->ass = ff_ass_get_dialog(ctx->readorder++, 0, is_subtitle_page ? "Subtitle" : "Teletext", NULL, buf.str); | |
| if (!sub_rect->ass) { | |
| av_bprint_finalize(&buf, NULL); | |
| return AVERROR(ENOMEM); | |
| } | |
| av_log(ctx, AV_LOG_DEBUG, "subtext:%s:txetbus\n", sub_rect->ass); | |
| } else { | |
| sub_rect->type = SUBTITLE_NONE; | |
| } | |
| av_bprint_finalize(&buf, NULL); | |
| return 0; | |
| } | |
| static void fix_transparency(TeletextContext *ctx, AVSubtitleRect *sub_rect, vbi_page *page, | |
| int chop_top, int resx, int resy) | |
| { | |
| int iy; | |
| // Hack for transparency, inspired by VLC code... | |
| for (iy = 0; iy < resy; iy++) { | |
| uint8_t *pixel = sub_rect->data[0] + iy * sub_rect->linesize[0]; | |
| vbi_char *vc = page->text + (iy / BITMAP_CHAR_HEIGHT + chop_top) * page->columns; | |
| vbi_char *vcnext = vc + page->columns; | |
| for (; vc < vcnext; vc++) { | |
| uint8_t *pixelnext = pixel + BITMAP_CHAR_WIDTH; | |
| switch (vc->opacity) { | |
| case VBI_TRANSPARENT_SPACE: | |
| memset(pixel, VBI_TRANSPARENT_BLACK, BITMAP_CHAR_WIDTH); | |
| break; | |
| case VBI_OPAQUE: | |
| if (!ctx->transparent_bg) | |
| break; | |
| case VBI_SEMI_TRANSPARENT: | |
| if (ctx->opacity > 0) { | |
| if (ctx->opacity < 255) | |
| for(; pixel < pixelnext; pixel++) | |
| if (*pixel == vc->background) | |
| *pixel += VBI_NB_COLORS; | |
| break; | |
| } | |
| case VBI_TRANSPARENT_FULL: | |
| for(; pixel < pixelnext; pixel++) | |
| if (*pixel == vc->background) | |
| *pixel = VBI_TRANSPARENT_BLACK; | |
| break; | |
| } | |
| pixel = pixelnext; | |
| } | |
| } | |
| } | |
| /* Draw a page as bitmap */ | |
| static int gen_sub_bitmap(TeletextContext *ctx, AVSubtitleRect *sub_rect, vbi_page *page, int chop_top) | |
| { | |
| int resx = page->columns * BITMAP_CHAR_WIDTH; | |
| int resy = (page->rows - chop_top) * BITMAP_CHAR_HEIGHT; | |
| uint8_t ci; | |
| vbi_char *vc = page->text + (chop_top * page->columns); | |
| vbi_char *vcend = page->text + (page->rows * page->columns); | |
| for (; vc < vcend; vc++) { | |
| if (vc->opacity != VBI_TRANSPARENT_SPACE) | |
| break; | |
| } | |
| if (vc >= vcend) { | |
| av_log(ctx, AV_LOG_DEBUG, "dropping empty page %3x\n", page->pgno); | |
| sub_rect->type = SUBTITLE_NONE; | |
| return 0; | |
| } | |
| sub_rect->data[0] = av_mallocz(resx * resy); | |
| sub_rect->linesize[0] = resx; | |
| if (!sub_rect->data[0]) | |
| return AVERROR(ENOMEM); | |
| vbi_draw_vt_page_region(page, VBI_PIXFMT_PAL8, | |
| sub_rect->data[0], sub_rect->linesize[0], | |
| 0, chop_top, page->columns, page->rows - chop_top, | |
| /*reveal*/ 1, /*flash*/ 1); | |
| fix_transparency(ctx, sub_rect, page, chop_top, resx, resy); | |
| sub_rect->x = ctx->x_offset; | |
| sub_rect->y = ctx->y_offset + chop_top * BITMAP_CHAR_HEIGHT; | |
| sub_rect->w = resx; | |
| sub_rect->h = resy; | |
| sub_rect->nb_colors = ctx->opacity > 0 && ctx->opacity < 255 ? 2 * VBI_NB_COLORS : VBI_NB_COLORS; | |
| sub_rect->data[1] = av_mallocz(AVPALETTE_SIZE); | |
| if (!sub_rect->data[1]) { | |
| av_freep(&sub_rect->data[0]); | |
| return AVERROR(ENOMEM); | |
| } | |
| for (ci = 0; ci < VBI_NB_COLORS; ci++) { | |
| int r, g, b, a; | |
| r = VBI_R(page->color_map[ci]); | |
| g = VBI_G(page->color_map[ci]); | |
| b = VBI_B(page->color_map[ci]); | |
| a = VBI_A(page->color_map[ci]); | |
| ((uint32_t *)sub_rect->data[1])[ci] = RGBA(r, g, b, a); | |
| ((uint32_t *)sub_rect->data[1])[ci + VBI_NB_COLORS] = RGBA(r, g, b, ctx->opacity); | |
| ff_dlog(ctx, "palette %0x\n", ((uint32_t *)sub_rect->data[1])[ci]); | |
| } | |
| ((uint32_t *)sub_rect->data[1])[VBI_TRANSPARENT_BLACK] = RGBA(0, 0, 0, 0); | |
| ((uint32_t *)sub_rect->data[1])[VBI_TRANSPARENT_BLACK + VBI_NB_COLORS] = RGBA(0, 0, 0, 0); | |
| sub_rect->type = SUBTITLE_BITMAP; | |
| return 0; | |
| } | |
| static void handler(vbi_event *ev, void *user_data) | |
| { | |
| TeletextContext *ctx = user_data; | |
| TeletextPage *new_pages; | |
| vbi_page page; | |
| int res; | |
| char pgno_str[12]; | |
| int chop_top; | |
| int is_subtitle_page = ctx->subtitle_map[ev->ev.ttx_page.pgno & 0x7ff]; | |
| snprintf(pgno_str, sizeof pgno_str, "%03x", ev->ev.ttx_page.pgno); | |
| av_log(ctx, AV_LOG_DEBUG, "decoded page %s.%02x\n", | |
| pgno_str, ev->ev.ttx_page.subno & 0xFF); | |
| if (strcmp(ctx->pgno, "*") && (strcmp(ctx->pgno, "subtitle") || !is_subtitle_page) && !strstr(ctx->pgno, pgno_str)) | |
| return; | |
| if (ctx->handler_ret < 0) | |
| return; | |
| res = vbi_fetch_vt_page(ctx->vbi, &page, | |
| ev->ev.ttx_page.pgno, | |
| ev->ev.ttx_page.subno, | |
| VBI_WST_LEVEL_3p5, 25, TRUE); | |
| if (!res) | |
| return; | |
| chop_top = ctx->chop_top || ((page.rows > 1) && is_subtitle_page); | |
| av_log(ctx, AV_LOG_DEBUG, "%d x %d page chop:%d\n", | |
| page.columns, page.rows, chop_top); | |
| if (ctx->nb_pages < MAX_BUFFERED_PAGES) { | |
| if ((new_pages = av_realloc_array(ctx->pages, ctx->nb_pages + 1, sizeof(TeletextPage)))) { | |
| TeletextPage *cur_page = new_pages + ctx->nb_pages; | |
| ctx->pages = new_pages; | |
| cur_page->sub_rect = av_mallocz(sizeof(*cur_page->sub_rect)); | |
| cur_page->pts = ctx->pts; | |
| cur_page->pgno = ev->ev.ttx_page.pgno; | |
| cur_page->subno = ev->ev.ttx_page.subno; | |
| if (cur_page->sub_rect) { | |
| switch (ctx->format_id) { | |
| case 0: | |
| res = gen_sub_bitmap(ctx, cur_page->sub_rect, &page, chop_top); | |
| break; | |
| case 1: | |
| res = gen_sub_text(ctx, cur_page->sub_rect, &page, chop_top); | |
| break; | |
| case 2: | |
| res = gen_sub_ass(ctx, cur_page->sub_rect, &page, chop_top); | |
| break; | |
| default: | |
| res = AVERROR_BUG; | |
| break; | |
| } | |
| if (res < 0) { | |
| av_freep(&cur_page->sub_rect); | |
| ctx->handler_ret = res; | |
| } else { | |
| ctx->pages[ctx->nb_pages++] = *cur_page; | |
| } | |
| } else { | |
| ctx->handler_ret = AVERROR(ENOMEM); | |
| } | |
| } else { | |
| ctx->handler_ret = AVERROR(ENOMEM); | |
| } | |
| } else { | |
| //TODO: If multiple packets contain more than one page, pages may got queued up, and this may happen... | |
| av_log(ctx, AV_LOG_ERROR, "Buffered too many pages, dropping page %s.\n", pgno_str); | |
| ctx->handler_ret = AVERROR(ENOSYS); | |
| } | |
| vbi_unref_page(&page); | |
| } | |
| static int slice_to_vbi_lines(TeletextContext *ctx, const uint8_t *buf, int size) | |
| { | |
| int lines = 0; | |
| while (size >= 2 && lines < MAX_SLICES) { | |
| int data_unit_id = buf[0]; | |
| int data_unit_length = buf[1]; | |
| if (data_unit_length + 2 > size) | |
| return AVERROR_INVALIDDATA; | |
| if (ff_data_unit_id_is_teletext(data_unit_id)) { | |
| if (data_unit_length != 0x2c) | |
| return AVERROR_INVALIDDATA; | |
| else { | |
| int line_offset = buf[2] & 0x1f; | |
| int field_parity = buf[2] & 0x20; | |
| uint8_t *p = ctx->sliced[lines].data; | |
| int i, pmag; | |
| ctx->sliced[lines].id = VBI_SLICED_TELETEXT_B; | |
| ctx->sliced[lines].line = (line_offset > 0 ? (line_offset + (field_parity ? 0 : 313)) : 0); | |
| for (i = 0; i < 42; i++) | |
| p[i] = vbi_rev8(buf[4 + i]); | |
| /* Unfortunately libzvbi does not expose page flags, and | |
| * vbi_classify_page only checks MIP, so we have to manually | |
| * decode the page flags and store the results. */ | |
| pmag = vbi_unham16p(p); | |
| if (pmag >= 0 && pmag >> 3 == 0) { // We found a row 0 header | |
| int page = vbi_unham16p(p + 2); | |
| int flags1 = vbi_unham16p(p + 6); | |
| int flags2 = vbi_unham16p(p + 8); | |
| if (page >= 0 && flags1 >= 0 && flags2 >= 0) { | |
| int pgno = ((pmag & 7) << 8) + page; | |
| // Check for disabled NEWSFLASH flag and enabled SUBTITLE and SUPRESS_HEADER flags | |
| ctx->subtitle_map[pgno] = (!(flags1 & 0x40) && flags1 & 0x80 && flags2 & 0x01); | |
| // Propagate ERASE_PAGE flag for repeated page headers to work around a libzvbi bug | |
| if (ctx->subtitle_map[pgno] && pgno == ctx->last_pgno) { | |
| int last_byte9 = vbi_unham8(ctx->last_p5); | |
| if (last_byte9 >= 0 && last_byte9 & 0x8) { | |
| int byte9 = vbi_unham8(p[5]); | |
| if (byte9 >= 0) | |
| p[5] = vbi_ham8(byte9 | 0x8); | |
| } | |
| } | |
| ctx->last_pgno = pgno; | |
| ctx->last_p5 = p[5]; | |
| } | |
| } | |
| lines++; | |
| } | |
| } | |
| size -= data_unit_length + 2; | |
| buf += data_unit_length + 2; | |
| } | |
| if (size) | |
| av_log(ctx, AV_LOG_WARNING, "%d bytes remained after slicing data\n", size); | |
| return lines; | |
| } | |
| static int teletext_decode_frame(AVCodecContext *avctx, AVSubtitle *sub, | |
| int *got_sub_ptr, const AVPacket *pkt) | |
| { | |
| TeletextContext *ctx = avctx->priv_data; | |
| int ret = 0; | |
| if (!ctx->vbi) { | |
| if (!(ctx->vbi = vbi_decoder_new())) | |
| return AVERROR(ENOMEM); | |
| if (ctx->default_region != -1) { | |
| av_log(avctx, AV_LOG_INFO, "Setting default zvbi region to %i\n", ctx->default_region); | |
| vbi_teletext_set_default_region(ctx->vbi, ctx->default_region); | |
| } | |
| if (!vbi_event_handler_register(ctx->vbi, VBI_EVENT_TTX_PAGE, handler, ctx)) { | |
| vbi_decoder_delete(ctx->vbi); | |
| ctx->vbi = NULL; | |
| return AVERROR(ENOMEM); | |
| } | |
| } | |
| if (avctx->pkt_timebase.num && pkt->pts != AV_NOPTS_VALUE) | |
| ctx->pts = av_rescale_q(pkt->pts, avctx->pkt_timebase, AV_TIME_BASE_Q); | |
| if (pkt->size) { | |
| int lines; | |
| const int full_pes_size = pkt->size + 45; /* PES header is 45 bytes */ | |
| // We allow unreasonably big packets, even if the standard only allows a max size of 1472 | |
| if (full_pes_size < 184 || full_pes_size > 65504 || full_pes_size % 184 != 0) | |
| return AVERROR_INVALIDDATA; | |
| ctx->handler_ret = pkt->size; | |
| if (ff_data_identifier_is_teletext(*pkt->data)) { | |
| if ((lines = slice_to_vbi_lines(ctx, pkt->data + 1, pkt->size - 1)) < 0) | |
| return lines; | |
| ff_dlog(avctx, "ctx=%p buf_size=%d lines=%u pkt_pts=%7.3f\n", | |
| ctx, pkt->size, lines, (double)pkt->pts/90000.0); | |
| if (lines > 0) { | |
| vbi_decode(ctx->vbi, ctx->sliced, lines, 0.0); | |
| ctx->lines_processed += lines; | |
| } | |
| } | |
| ctx->pts = AV_NOPTS_VALUE; | |
| ret = ctx->handler_ret; | |
| } | |
| if (ret < 0) | |
| return ret; | |
| // is there a subtitle to pass? | |
| if (ctx->nb_pages) { | |
| int i; | |
| sub->format = !!ctx->format_id; | |
| sub->start_display_time = 0; | |
| sub->end_display_time = ctx->sub_duration; | |
| sub->num_rects = 0; | |
| sub->pts = ctx->pages->pts; | |
| if (ctx->pages->sub_rect->type != SUBTITLE_NONE) { | |
| sub->rects = av_malloc(sizeof(*sub->rects)); | |
| if (sub->rects) { | |
| sub->num_rects = 1; | |
| sub->rects[0] = ctx->pages->sub_rect; | |
| } else { | |
| ret = AVERROR(ENOMEM); | |
| } | |
| } else { | |
| av_log(avctx, AV_LOG_DEBUG, "sending empty sub\n"); | |
| sub->rects = NULL; | |
| } | |
| if (!sub->rects) // no rect was passed | |
| subtitle_rect_free(&ctx->pages->sub_rect); | |
| for (i = 0; i < ctx->nb_pages - 1; i++) | |
| ctx->pages[i] = ctx->pages[i + 1]; | |
| ctx->nb_pages--; | |
| if (ret >= 0) | |
| *got_sub_ptr = 1; | |
| } else | |
| *got_sub_ptr = 0; | |
| return ret; | |
| } | |
| static int teletext_init_decoder(AVCodecContext *avctx) | |
| { | |
| TeletextContext *ctx = avctx->priv_data; | |
| unsigned int maj, min, rev; | |
| vbi_version(&maj, &min, &rev); | |
| if (!(maj > 0 || min > 2 || min == 2 && rev >= 26)) { | |
| av_log(avctx, AV_LOG_ERROR, "decoder needs zvbi version >= 0.2.26.\n"); | |
| return AVERROR_EXTERNAL; | |
| } | |
| if (ctx->format_id == 0) { | |
| avctx->width = 41 * BITMAP_CHAR_WIDTH; | |
| avctx->height = 25 * BITMAP_CHAR_HEIGHT; | |
| } | |
| ctx->vbi = NULL; | |
| ctx->pts = AV_NOPTS_VALUE; | |
| ctx->last_pgno = -1; | |
| ctx->last_ass_alignment = 2; | |
| if (ctx->opacity == -1) | |
| ctx->opacity = ctx->transparent_bg ? 0 : 255; | |
| av_log(avctx, AV_LOG_VERBOSE, "page filter: %s\n", ctx->pgno); | |
| switch (ctx->format_id) { | |
| case 0: | |
| return 0; | |
| case 1: | |
| return ff_ass_subtitle_header_default(avctx); | |
| case 2: | |
| return my_ass_subtitle_header(avctx); | |
| } | |
| return AVERROR_BUG; | |
| } | |
| static int teletext_close_decoder(AVCodecContext *avctx) | |
| { | |
| TeletextContext *ctx = avctx->priv_data; | |
| ff_dlog(avctx, "lines_total=%u\n", ctx->lines_processed); | |
| while (ctx->nb_pages) | |
| subtitle_rect_free(&ctx->pages[--ctx->nb_pages].sub_rect); | |
| av_freep(&ctx->pages); | |
| vbi_decoder_delete(ctx->vbi); | |
| ctx->vbi = NULL; | |
| ctx->pts = AV_NOPTS_VALUE; | |
| ctx->last_pgno = -1; | |
| ctx->last_ass_alignment = 2; | |
| memset(ctx->subtitle_map, 0, sizeof(ctx->subtitle_map)); | |
| if (!(avctx->flags2 & AV_CODEC_FLAG2_RO_FLUSH_NOOP)) | |
| ctx->readorder = 0; | |
| return 0; | |
| } | |
| static void teletext_flush(AVCodecContext *avctx) | |
| { | |
| teletext_close_decoder(avctx); | |
| } | |
| #define OFFSET(x) offsetof(TeletextContext, x) | |
| #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM | |
| static const AVOption options[] = { | |
| {"txt_page", "page numbers to decode, subtitle for subtitles, * for all", OFFSET(pgno), AV_OPT_TYPE_STRING, {.str = "*"}, 0, 0, SD}, | |
| {"txt_default_region", "default G0 character set used for decoding", OFFSET(default_region), AV_OPT_TYPE_INT, {.i64 = -1}, -1, 87, SD}, | |
| {"txt_chop_top", "discards the top teletext line", OFFSET(chop_top), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, SD}, | |
| {"txt_format", "format of the subtitles (bitmap or text or ass)", OFFSET(format_id), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 2, SD, .unit = "txt_format"}, | |
| {"bitmap", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 0}, 0, 0, SD, .unit = "txt_format"}, | |
| {"text", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 1}, 0, 0, SD, .unit = "txt_format"}, | |
| {"ass", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 2}, 0, 0, SD, .unit = "txt_format"}, | |
| {"txt_left", "x offset of generated bitmaps", OFFSET(x_offset), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 65535, SD}, | |
| {"txt_top", "y offset of generated bitmaps", OFFSET(y_offset), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 65535, SD}, | |
| {"txt_chop_spaces", "chops leading and trailing spaces from text", OFFSET(chop_spaces), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, SD}, | |
| {"txt_duration", "display duration of teletext pages in msecs", OFFSET(sub_duration), AV_OPT_TYPE_INT, {.i64 = -1}, -1, 86400000, SD}, | |
| {"txt_transparent", "force transparent background of the teletext", OFFSET(transparent_bg), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, SD}, | |
| {"txt_opacity", "set opacity of the transparent background", OFFSET(opacity), AV_OPT_TYPE_INT, {.i64 = -1}, -1, 255, SD}, | |
| { NULL }, | |
| }; | |
| static const AVClass teletext_class = { | |
| .class_name = "libzvbi_teletextdec", | |
| .item_name = av_default_item_name, | |
| .option = options, | |
| .version = LIBAVUTIL_VERSION_INT, | |
| }; | |
| const FFCodec ff_libzvbi_teletext_decoder = { | |
| .p.name = "libzvbi_teletextdec", | |
| CODEC_LONG_NAME("Libzvbi DVB teletext decoder"), | |
| .p.type = AVMEDIA_TYPE_SUBTITLE, | |
| .p.id = AV_CODEC_ID_DVB_TELETEXT, | |
| .p.capabilities = AV_CODEC_CAP_DELAY, | |
| .p.priv_class = &teletext_class, | |
| .p.wrapper_name = "libzvbi", | |
| .caps_internal = FF_CODEC_CAP_NOT_INIT_THREADSAFE, | |
| .priv_data_size = sizeof(TeletextContext), | |
| .init = teletext_init_decoder, | |
| .close = teletext_close_decoder, | |
| FF_CODEC_DECODE_SUB_CB(teletext_decode_frame), | |
| .flush = teletext_flush, | |
| }; |