| /* |
| * 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 "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, 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, void *data, int *got_sub_ptr, AVPacket *pkt) |
| { |
| TeletextContext *ctx = avctx->priv_data; |
| AVSubtitle *sub = data; |
| int ret = 0; |
| int j; |
| |
| 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; |
| #if FF_API_AVPICTURE |
| FF_DISABLE_DEPRECATION_WARNINGS |
| for (j = 0; j < 4; j++) { |
| sub->rects[0]->pict.data[j] = sub->rects[0]->data[j]; |
| sub->rects[0]->pict.linesize[j] = sub->rects[0]->linesize[j]; |
| } |
| FF_ENABLE_DEPRECATION_WARNINGS |
| #endif |
| } 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, "txt_format"}, |
| {"bitmap", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 0}, 0, 0, SD, "txt_format"}, |
| {"text", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 1}, 0, 0, SD, "txt_format"}, |
| {"ass", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 2}, 0, 0, SD, "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, |
| }; |
| |
| AVCodec ff_libzvbi_teletext_decoder = { |
| .name = "libzvbi_teletextdec", |
| .long_name = NULL_IF_CONFIG_SMALL("Libzvbi DVB teletext decoder"), |
| .type = AVMEDIA_TYPE_SUBTITLE, |
| .id = AV_CODEC_ID_DVB_TELETEXT, |
| .priv_data_size = sizeof(TeletextContext), |
| .init = teletext_init_decoder, |
| .close = teletext_close_decoder, |
| .decode = teletext_decode_frame, |
| .capabilities = AV_CODEC_CAP_DELAY, |
| .flush = teletext_flush, |
| .priv_class= &teletext_class, |
| .wrapper_name = "libzvbi", |
| }; |
