/* * 3GPP TS 26.245 Timed Text encoder * Copyright (c) 2012 Philip Langdale * * 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 #include "avcodec.h" #include "libavutil/opt.h" #include "libavutil/avassert.h" #include "libavutil/avstring.h" #include "libavutil/intreadwrite.h" #include "libavutil/mem.h" #include "libavutil/common.h" #include "ass_split.h" #include "ass.h" #define STYLE_FLAG_BOLD (1<<0) #define STYLE_FLAG_ITALIC (1<<1) #define STYLE_FLAG_UNDERLINE (1<<2) #define STYLE_RECORD_SIZE 12 #define SIZE_ADD 10 #define STYL_BOX (1<<0) #define HLIT_BOX (1<<1) #define HCLR_BOX (1<<2) #define DEFAULT_STYLE_FONT_ID 0x01 #define DEFAULT_STYLE_FONTSIZE 0x12 #define DEFAULT_STYLE_COLOR 0xffffffff #define DEFAULT_STYLE_FLAG 0x00 #define BGR_TO_RGB(c) (((c) & 0xff) << 16 | ((c) & 0xff00) | (((c) >> 16) & 0xff)) #define FONTSIZE_SCALE(s,fs) ((fs) * (s)->font_scale_factor + 0.5) #define av_bprint_append_any(buf, data, size) av_bprint_append_data(buf, ((const char*)data), size) typedef struct { uint16_t style_start; uint16_t style_end; uint8_t style_flag; uint16_t style_fontID; uint8_t style_fontsize; uint32_t style_color; } StyleBox; typedef struct { uint16_t start; uint16_t end; } HighlightBox; typedef struct { uint32_t color; } HilightcolorBox; typedef struct { AVClass *class; AVCodecContext *avctx; ASSSplitContext *ass_ctx; ASSStyle *ass_dialog_style; AVBPrint buffer; StyleBox **style_attributes; StyleBox *style_attributes_temp; HighlightBox hlit; HilightcolorBox hclr; int count; uint8_t box_flags; StyleBox d; uint16_t text_pos; uint16_t byte_count; char ** fonts; int font_count; double font_scale_factor; int frame_height; } MovTextContext; typedef struct { uint32_t type; void (*encode)(MovTextContext *s, uint32_t tsmb_type); } Box; static void mov_text_cleanup(MovTextContext *s) { int j; if (s->box_flags & STYL_BOX) { for (j = 0; j < s->count; j++) { av_freep(&s->style_attributes[j]); } av_freep(&s->style_attributes); } if (s->style_attributes_temp) { *s->style_attributes_temp = s->d; } } static void encode_styl(MovTextContext *s, uint32_t tsmb_type) { int j; uint32_t tsmb_size; uint16_t style_entries; if ((s->box_flags & STYL_BOX) && s->count) { tsmb_size = s->count * STYLE_RECORD_SIZE + SIZE_ADD; tsmb_size = AV_RB32(&tsmb_size); style_entries = AV_RB16(&s->count); /*The above three attributes are hard coded for now but will come from ASS style in the future*/ av_bprint_append_any(&s->buffer, &tsmb_size, 4); av_bprint_append_any(&s->buffer, &tsmb_type, 4); av_bprint_append_any(&s->buffer, &style_entries, 2); for (j = 0; j < s->count; j++) { uint16_t style_start, style_end, style_fontID; uint32_t style_color; style_start = AV_RB16(&s->style_attributes[j]->style_start); style_end = AV_RB16(&s->style_attributes[j]->style_end); style_color = AV_RB32(&s->style_attributes[j]->style_color); style_fontID = AV_RB16(&s->style_attributes[j]->style_fontID); av_bprint_append_any(&s->buffer, &style_start, 2); av_bprint_append_any(&s->buffer, &style_end, 2); av_bprint_append_any(&s->buffer, &style_fontID, 2); av_bprint_append_any(&s->buffer, &s->style_attributes[j]->style_flag, 1); av_bprint_append_any(&s->buffer, &s->style_attributes[j]->style_fontsize, 1); av_bprint_append_any(&s->buffer, &style_color, 4); } } mov_text_cleanup(s); } static void encode_hlit(MovTextContext *s, uint32_t tsmb_type) { uint32_t tsmb_size; uint16_t start, end; if (s->box_flags & HLIT_BOX) { tsmb_size = 12; tsmb_size = AV_RB32(&tsmb_size); start = AV_RB16(&s->hlit.start); end = AV_RB16(&s->hlit.end); av_bprint_append_any(&s->buffer, &tsmb_size, 4); av_bprint_append_any(&s->buffer, &tsmb_type, 4); av_bprint_append_any(&s->buffer, &start, 2); av_bprint_append_any(&s->buffer, &end, 2); } } static void encode_hclr(MovTextContext *s, uint32_t tsmb_type) { uint32_t tsmb_size, color; if (s->box_flags & HCLR_BOX) { tsmb_size = 12; tsmb_size = AV_RB32(&tsmb_size); color = AV_RB32(&s->hclr.color); av_bprint_append_any(&s->buffer, &tsmb_size, 4); av_bprint_append_any(&s->buffer, &tsmb_type, 4); av_bprint_append_any(&s->buffer, &color, 4); } } static const Box box_types[] = { { MKTAG('s','t','y','l'), encode_styl }, { MKTAG('h','l','i','t'), encode_hlit }, { MKTAG('h','c','l','r'), encode_hclr }, }; const static size_t box_count = FF_ARRAY_ELEMS(box_types); static int mov_text_encode_close(AVCodecContext *avctx) { MovTextContext *s = avctx->priv_data; int i; ff_ass_split_free(s->ass_ctx); if (s->style_attributes) { for (i = 0; i < s->count; i++) { av_freep(&s->style_attributes[i]); } av_freep(&s->style_attributes); } av_freep(&s->fonts); av_freep(&s->style_attributes_temp); av_bprint_finalize(&s->buffer, NULL); return 0; } static int encode_sample_description(AVCodecContext *avctx) { ASS * ass; ASSStyle * style; int i, j; uint32_t tsmb_size, tsmb_type, back_color, style_color; uint16_t style_start, style_end, fontID, count; int font_names_total_len = 0; MovTextContext *s = avctx->priv_data; static const uint8_t display_and_justification[] = { 0x00, 0x00, 0x00, 0x00, // uint32_t displayFlags 0x01, // int8_t horizontal-justification 0xFF, // int8_t vertical-justification }; // 0x00, 0x00, 0x00, 0x00, // uint8_t background-color-rgba[4] static const uint8_t box_record[] = { // BoxRecord { 0x00, 0x00, // int16_t top 0x00, 0x00, // int16_t left 0x00, 0x00, // int16_t bottom 0x00, 0x00, // int16_t right // }; }; // StyleRecord { // 0x00, 0x00, // uint16_t startChar // 0x00, 0x00, // uint16_t endChar // 0x00, 0x01, // uint16_t font-ID // 0x00, // uint8_t face-style-flags // 0x12, // uint8_t font-size // 0xFF, 0xFF, 0xFF, 0xFF, // uint8_t text-color-rgba[4] // }; // FontTableBox { // 0x00, 0x00, 0x00, 0x12, // uint32_t size // 'f', 't', 'a', 'b', // uint8_t name[4] // 0x00, 0x01, // uint16_t entry-count // FontRecord { // 0x00, 0x01, // uint16_t font-ID // 0x05, // uint8_t font-name-length // 'S', 'e', 'r', 'i', 'f',// uint8_t font[font-name-length] // }; // }; // Populate sample description from ASS header ass = (ASS*)s->ass_ctx; // Compute font scaling factor based on (optionally) provided // output video height and ASS script play_res_y if (s->frame_height && ass->script_info.play_res_y) s->font_scale_factor = (double)s->frame_height / ass->script_info.play_res_y; else s->font_scale_factor = 1; style = ff_ass_style_get(s->ass_ctx, "Default"); if (!style && ass->styles_count) { style = &ass->styles[0]; } s->d.style_fontID = DEFAULT_STYLE_FONT_ID; s->d.style_fontsize = DEFAULT_STYLE_FONTSIZE; s->d.style_color = DEFAULT_STYLE_COLOR; s->d.style_flag = DEFAULT_STYLE_FLAG; if (style) { s->d.style_fontsize = FONTSIZE_SCALE(s, style->font_size); s->d.style_color = BGR_TO_RGB(style->primary_color & 0xffffff) << 8 | 255 - ((uint32_t)style->primary_color >> 24); s->d.style_flag = (!!style->bold * STYLE_FLAG_BOLD) | (!!style->italic * STYLE_FLAG_ITALIC) | (!!style->underline * STYLE_FLAG_UNDERLINE); back_color = (BGR_TO_RGB(style->back_color & 0xffffff) << 8) | (255 - ((uint32_t)style->back_color >> 24)); } av_bprint_append_any(&s->buffer, display_and_justification, sizeof(display_and_justification)); back_color = AV_RB32(&back_color); av_bprint_append_any(&s->buffer, &back_color, 4); // BoxRecord { av_bprint_append_any(&s->buffer, box_record, sizeof(box_record)); // }; // StyleRecord { style_start = AV_RB16(&s->d.style_start); style_end = AV_RB16(&s->d.style_end); fontID = AV_RB16(&s->d.style_fontID); style_color = AV_RB32(&s->d.style_color); av_bprint_append_any(&s->buffer, &style_start, 2); av_bprint_append_any(&s->buffer, &style_end, 2); av_bprint_append_any(&s->buffer, &fontID, 2); av_bprint_append_any(&s->buffer, &s->d.style_flag, 1); av_bprint_append_any(&s->buffer, &s->d.style_fontsize, 1); av_bprint_append_any(&s->buffer, &style_color, 4); // }; // Build font table // We can't build a complete font table since that would require // scanning all dialogs first. But we can at least fill in what // is avaiable in the ASS header if (style && ass->styles_count) { // Find unique font names av_dynarray_add(&s->fonts, &s->font_count, style->font_name); font_names_total_len += strlen(style->font_name); for (i = 0; i < ass->styles_count; i++) { int found = 0; for (j = 0; j < s->font_count; j++) { if (!strcmp(s->fonts[j], ass->styles[i].font_name)) { found = 1; break; } } if (!found) { av_dynarray_add(&s->fonts, &s->font_count, ass->styles[i].font_name); font_names_total_len += strlen(ass->styles[i].font_name); } } } else av_dynarray_add(&s->fonts, &s->font_count, (char*)"Serif"); // FontTableBox { tsmb_size = SIZE_ADD + 3 * s->font_count + font_names_total_len; tsmb_size = AV_RB32(&tsmb_size); tsmb_type = MKTAG('f','t','a','b'); count = AV_RB16(&s->font_count); av_bprint_append_any(&s->buffer, &tsmb_size, 4); av_bprint_append_any(&s->buffer, &tsmb_type, 4); av_bprint_append_any(&s->buffer, &count, 2); // FontRecord { for (i = 0; i < s->font_count; i++) { int len; fontID = i + 1; fontID = AV_RB16(&fontID); av_bprint_append_any(&s->buffer, &fontID, 2); len = strlen(s->fonts[i]); av_bprint_append_any(&s->buffer, &len, 1); av_bprint_append_any(&s->buffer, s->fonts[i], len); } // }; // }; if (!av_bprint_is_complete(&s->buffer)) { return AVERROR(ENOMEM); } avctx->extradata_size = s->buffer.len; avctx->extradata = av_mallocz(avctx->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE); if (!avctx->extradata) { return AVERROR(ENOMEM); } memcpy(avctx->extradata, s->buffer.str, avctx->extradata_size); av_bprint_clear(&s->buffer); return 0; } static av_cold int mov_text_encode_init(AVCodecContext *avctx) { int ret; MovTextContext *s = avctx->priv_data; s->avctx = avctx; av_bprint_init(&s->buffer, 0, AV_BPRINT_SIZE_UNLIMITED); s->style_attributes_temp = av_mallocz(sizeof(*s->style_attributes_temp)); if (!s->style_attributes_temp) { ret = AVERROR(ENOMEM); goto fail; } s->ass_ctx = ff_ass_split(avctx->subtitle_header); if (!s->ass_ctx) { ret = AVERROR_INVALIDDATA; goto fail; } ret = encode_sample_description(avctx); if (ret < 0) goto fail; return 0; fail: mov_text_encode_close(avctx); return ret; } // Start a new style box if needed static int mov_text_style_start(MovTextContext *s) { // there's an existing style entry if (s->style_attributes_temp->style_start == s->text_pos) // Still at same text pos, use same entry return 1; if (s->style_attributes_temp->style_flag != s->d.style_flag || s->style_attributes_temp->style_color != s->d.style_color || s->style_attributes_temp->style_fontID != s->d.style_fontID || s->style_attributes_temp->style_fontsize != s->d.style_fontsize) { // last style != defaults, end the style entry and start a new one s->box_flags |= STYL_BOX; s->style_attributes_temp->style_end = s->text_pos; av_dynarray_add(&s->style_attributes, &s->count, s->style_attributes_temp); s->style_attributes_temp = av_malloc(sizeof(*s->style_attributes_temp)); if (!s->style_attributes_temp) { mov_text_cleanup(s); av_bprint_clear(&s->buffer); s->box_flags &= ~STYL_BOX; return 0; } *s->style_attributes_temp = s->d; s->style_attributes_temp->style_start = s->text_pos; } else { // style entry matches defaults, drop entry *s->style_attributes_temp = s->d; s->style_attributes_temp->style_start = s->text_pos; } return 1; } static uint8_t mov_text_style_to_flag(const char style) { uint8_t style_flag = 0; switch (style){ case 'b': style_flag = STYLE_FLAG_BOLD; break; case 'i': style_flag = STYLE_FLAG_ITALIC; break; case 'u': style_flag = STYLE_FLAG_UNDERLINE; break; } return style_flag; } static void mov_text_style_set(MovTextContext *s, uint8_t style_flags) { if (!s->style_attributes_temp || !((s->style_attributes_temp->style_flag & style_flags) ^ style_flags)) { // setting flags that that are already set return; } if (mov_text_style_start(s)) s->style_attributes_temp->style_flag |= style_flags; } static void mov_text_style_cb(void *priv, const char style, int close) { MovTextContext *s = priv; uint8_t style_flag = mov_text_style_to_flag(style); if (!s->style_attributes_temp || !!(s->style_attributes_temp->style_flag & style_flag) != close) { // setting flag that is already set return; } if (mov_text_style_start(s)) { if (!close) s->style_attributes_temp->style_flag |= style_flag; else s->style_attributes_temp->style_flag &= ~style_flag; } } static void mov_text_color_set(MovTextContext *s, uint32_t color) { if (!s->style_attributes_temp || (s->style_attributes_temp->style_color & 0xffffff00) == color) { // color hasn't changed return; } if (mov_text_style_start(s)) s->style_attributes_temp->style_color = (color & 0xffffff00) | (s->style_attributes_temp->style_color & 0xff); } static void mov_text_color_cb(void *priv, unsigned int color, unsigned int color_id) { MovTextContext *s = priv; color = BGR_TO_RGB(color) << 8; if (color_id == 1) { //primary color changes mov_text_color_set(s, color); } else if (color_id == 2) { //secondary color changes if (!(s->box_flags & HCLR_BOX)) // Highlight alpha not set yet, use current primary alpha s->hclr.color = s->style_attributes_temp->style_color; if (!(s->box_flags & HLIT_BOX) || s->hlit.start == s->text_pos) { s->box_flags |= HCLR_BOX; s->box_flags |= HLIT_BOX; s->hlit.start = s->text_pos; s->hclr.color = color | (s->hclr.color & 0xFF); } else //close tag s->hlit.end = s->text_pos; /* If there are more than one secondary color changes in ASS, take start of first section and end of last section. Movtext allows only one highlight box per sample. */ } // Movtext does not support changes to other color_id (outline, background) } static void mov_text_alpha_set(MovTextContext *s, uint8_t alpha) { if (!s->style_attributes_temp || (s->style_attributes_temp->style_color & 0xff) == alpha) { // color hasn't changed return; } if (mov_text_style_start(s)) s->style_attributes_temp->style_color = (s->style_attributes_temp->style_color & 0xffffff00) | alpha; } static void mov_text_alpha_cb(void *priv, int alpha, int alpha_id) { MovTextContext *s = priv; alpha = 255 - alpha; if (alpha_id == 1) // primary alpha changes mov_text_alpha_set(s, alpha); else if (alpha_id == 2) { //secondary alpha changes if (!(s->box_flags & HCLR_BOX)) // Highlight color not set yet, use current primary color s->hclr.color = s->style_attributes_temp->style_color; if (!(s->box_flags & HLIT_BOX) || s->hlit.start == s->text_pos) { s->box_flags |= HCLR_BOX; s->box_flags |= HLIT_BOX; s->hlit.start = s->text_pos; s->hclr.color = (s->hclr.color & 0xffffff00) | alpha; } else //close tag s->hlit.end = s->text_pos; } // Movtext does not support changes to other alpha_id (outline, background) } static uint16_t find_font_id(MovTextContext * s, const char * name) { int i; for (i = 0; i < s->font_count; i++) { if (!strcmp(name, s->fonts[i])) return i + 1; } return 1; } static void mov_text_font_name_set(MovTextContext *s, const char *name) { int fontID = find_font_id(s, name); if (!s->style_attributes_temp || s->style_attributes_temp->style_fontID == fontID) { // color hasn't changed return; } if (mov_text_style_start(s)) s->style_attributes_temp->style_fontID = fontID; } static void mov_text_font_name_cb(void *priv, const char *name) { mov_text_font_name_set((MovTextContext*)priv, name); } static void mov_text_font_size_set(MovTextContext *s, int size) { size = FONTSIZE_SCALE(s, size); if (!s->style_attributes_temp || s->style_attributes_temp->style_fontsize == size) { // color hasn't changed return; } if (mov_text_style_start(s)) s->style_attributes_temp->style_fontsize = size; } static void mov_text_font_size_cb(void *priv, int size) { mov_text_font_size_set((MovTextContext*)priv, size); } static void mov_text_end_cb(void *priv) { // End of text, close any open style record mov_text_style_start((MovTextContext*)priv); } static void mov_text_ass_style_set(MovTextContext *s, ASSStyle *style) { uint8_t style_flags, alpha; uint32_t color; if (style) { style_flags = (!!style->bold * STYLE_FLAG_BOLD) | (!!style->italic * STYLE_FLAG_ITALIC) | (!!style->underline * STYLE_FLAG_UNDERLINE); mov_text_style_set(s, style_flags); color = BGR_TO_RGB(style->primary_color & 0xffffff) << 8; mov_text_color_set(s, color); alpha = 255 - ((uint32_t)style->primary_color >> 24); mov_text_alpha_set(s, alpha); mov_text_font_size_set(s, style->font_size); mov_text_font_name_set(s, style->font_name); } else { // End current style record, go back to defaults mov_text_style_start(s); } } static void mov_text_dialog(MovTextContext *s, ASSDialog *dialog) { ASSStyle * style = ff_ass_style_get(s->ass_ctx, dialog->style); s->ass_dialog_style = style; mov_text_ass_style_set(s, style); } static void mov_text_cancel_overrides_cb(void *priv, const char * style_name) { MovTextContext *s = priv; ASSStyle * style; if (!style_name || !*style_name) style = s->ass_dialog_style; else style= ff_ass_style_get(s->ass_ctx, style_name); mov_text_ass_style_set(s, style); } static uint16_t utf8_strlen(const char *text, int len) { uint16_t i = 0, ret = 0; while (i < len) { char c = text[i]; if ((c & 0x80) == 0) i += 1; else if ((c & 0xE0) == 0xC0) i += 2; else if ((c & 0xF0) == 0xE0) i += 3; else if ((c & 0xF8) == 0xF0) i += 4; else return 0; ret++; } return ret; } static void mov_text_text_cb(void *priv, const char *text, int len) { uint16_t utf8_len = utf8_strlen(text, len); MovTextContext *s = priv; av_bprint_append_data(&s->buffer, text, len); // If it's not utf-8, just use the byte length s->text_pos += utf8_len ? utf8_len : len; s->byte_count += len; } static void mov_text_new_line_cb(void *priv, int forced) { MovTextContext *s = priv; av_bprint_append_data(&s->buffer, "\n", 1); s->text_pos += 1; s->byte_count += 1; } static const ASSCodesCallbacks mov_text_callbacks = { .text = mov_text_text_cb, .new_line = mov_text_new_line_cb, .style = mov_text_style_cb, .color = mov_text_color_cb, .alpha = mov_text_alpha_cb, .font_name = mov_text_font_name_cb, .font_size = mov_text_font_size_cb, .cancel_overrides = mov_text_cancel_overrides_cb, .end = mov_text_end_cb, }; static int mov_text_encode_frame(AVCodecContext *avctx, unsigned char *buf, int bufsize, const AVSubtitle *sub) { MovTextContext *s = avctx->priv_data; ASSDialog *dialog; int i, length; size_t j; s->byte_count = 0; s->text_pos = 0; s->count = 0; s->box_flags = 0; for (i = 0; i < sub->num_rects; i++) { const char *ass = sub->rects[i]->ass; if (sub->rects[i]->type != SUBTITLE_ASS) { av_log(avctx, AV_LOG_ERROR, "Only SUBTITLE_ASS type supported.\n"); return AVERROR(EINVAL); } #if FF_API_ASS_TIMING if (!strncmp(ass, "Dialogue: ", 10)) { int num; dialog = ff_ass_split_dialog(s->ass_ctx, ass, 0, &num); for (; dialog && num--; dialog++) { mov_text_dialog(s, dialog); ff_ass_split_override_codes(&mov_text_callbacks, s, dialog->text); } } else { #endif dialog = ff_ass_split_dialog2(s->ass_ctx, ass); if (!dialog) return AVERROR(ENOMEM); mov_text_dialog(s, dialog); ff_ass_split_override_codes(&mov_text_callbacks, s, dialog->text); ff_ass_free_dialog(&dialog); #if FF_API_ASS_TIMING } #endif for (j = 0; j < box_count; j++) { box_types[j].encode(s, box_types[j].type); } } AV_WB16(buf, s->byte_count); buf += 2; if (!av_bprint_is_complete(&s->buffer)) { length = AVERROR(ENOMEM); goto exit; } if (!s->buffer.len) { length = 0; goto exit; } if (s->buffer.len > bufsize - 3) { av_log(avctx, AV_LOG_ERROR, "Buffer too small for ASS event.\n"); length = AVERROR_BUFFER_TOO_SMALL; goto exit; } memcpy(buf, s->buffer.str, s->buffer.len); length = s->buffer.len + 2; exit: av_bprint_clear(&s->buffer); return length; } #define OFFSET(x) offsetof(MovTextContext, x) #define FLAGS AV_OPT_FLAG_ENCODING_PARAM | AV_OPT_FLAG_SUBTITLE_PARAM static const AVOption options[] = { { "height", "Frame height, usually video height", OFFSET(frame_height), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS }, { NULL }, }; static const AVClass mov_text_encoder_class = { .class_name = "MOV text enoder", .item_name = av_default_item_name, .option = options, .version = LIBAVUTIL_VERSION_INT, }; AVCodec ff_movtext_encoder = { .name = "mov_text", .long_name = NULL_IF_CONFIG_SMALL("3GPP Timed Text subtitle"), .type = AVMEDIA_TYPE_SUBTITLE, .id = AV_CODEC_ID_MOV_TEXT, .priv_data_size = sizeof(MovTextContext), .priv_class = &mov_text_encoder_class, .init = mov_text_encode_init, .encode_sub = mov_text_encode_frame, .close = mov_text_encode_close, };