| /* |
| * SubRip subtitle encoder |
| * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org> |
| * |
| * 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 <stdarg.h> |
| #include "avcodec.h" |
| #include "libavutil/avstring.h" |
| #include "libavutil/bprint.h" |
| #include "ass_split.h" |
| #include "ass.h" |
| |
| |
| #define SRT_STACK_SIZE 64 |
| |
| typedef struct { |
| AVCodecContext *avctx; |
| ASSSplitContext *ass_ctx; |
| AVBPrint buffer; |
| char stack[SRT_STACK_SIZE]; |
| int stack_ptr; |
| int alignment_applied; |
| } SRTContext; |
| |
| |
| #ifdef __GNUC__ |
| __attribute__ ((__format__ (__printf__, 2, 3))) |
| #endif |
| static void srt_print(SRTContext *s, const char *str, ...) |
| { |
| va_list vargs; |
| va_start(vargs, str); |
| av_vbprintf(&s->buffer, str, vargs); |
| va_end(vargs); |
| } |
| |
| static int srt_stack_push(SRTContext *s, const char c) |
| { |
| if (s->stack_ptr >= SRT_STACK_SIZE) |
| return -1; |
| s->stack[s->stack_ptr++] = c; |
| return 0; |
| } |
| |
| static char srt_stack_pop(SRTContext *s) |
| { |
| if (s->stack_ptr <= 0) |
| return 0; |
| return s->stack[--s->stack_ptr]; |
| } |
| |
| static int srt_stack_find(SRTContext *s, const char c) |
| { |
| int i; |
| for (i = s->stack_ptr-1; i >= 0; i--) |
| if (s->stack[i] == c) |
| break; |
| return i; |
| } |
| |
| static void srt_close_tag(SRTContext *s, char tag) |
| { |
| srt_print(s, "</%c%s>", tag, tag == 'f' ? "ont" : ""); |
| } |
| |
| static void srt_stack_push_pop(SRTContext *s, const char c, int close) |
| { |
| if (close) { |
| int i = c ? srt_stack_find(s, c) : 0; |
| if (i < 0) |
| return; |
| while (s->stack_ptr != i) |
| srt_close_tag(s, srt_stack_pop(s)); |
| } else if (srt_stack_push(s, c) < 0) |
| av_log(s->avctx, AV_LOG_ERROR, "tag stack overflow\n"); |
| } |
| |
| static void srt_style_apply(SRTContext *s, const char *style) |
| { |
| ASSStyle *st = ff_ass_style_get(s->ass_ctx, style); |
| if (st) { |
| int c = st->primary_color & 0xFFFFFF; |
| if (st->font_name && strcmp(st->font_name, ASS_DEFAULT_FONT) || |
| st->font_size != ASS_DEFAULT_FONT_SIZE || |
| c != ASS_DEFAULT_COLOR) { |
| srt_print(s, "<font"); |
| if (st->font_name && strcmp(st->font_name, ASS_DEFAULT_FONT)) |
| srt_print(s, " face=\"%s\"", st->font_name); |
| if (st->font_size != ASS_DEFAULT_FONT_SIZE) |
| srt_print(s, " size=\"%d\"", st->font_size); |
| if (c != ASS_DEFAULT_COLOR) |
| srt_print(s, " color=\"#%06x\"", |
| (c & 0xFF0000) >> 16 | c & 0xFF00 | (c & 0xFF) << 16); |
| srt_print(s, ">"); |
| srt_stack_push(s, 'f'); |
| } |
| if (st->bold != ASS_DEFAULT_BOLD) { |
| srt_print(s, "<b>"); |
| srt_stack_push(s, 'b'); |
| } |
| if (st->italic != ASS_DEFAULT_ITALIC) { |
| srt_print(s, "<i>"); |
| srt_stack_push(s, 'i'); |
| } |
| if (st->underline != ASS_DEFAULT_UNDERLINE) { |
| srt_print(s, "<u>"); |
| srt_stack_push(s, 'u'); |
| } |
| if (st->alignment != ASS_DEFAULT_ALIGNMENT) { |
| srt_print(s, "{\\an%d}", st->alignment); |
| s->alignment_applied = 1; |
| } |
| } |
| } |
| |
| |
| static av_cold int srt_encode_init(AVCodecContext *avctx) |
| { |
| SRTContext *s = avctx->priv_data; |
| s->avctx = avctx; |
| s->ass_ctx = ff_ass_split(avctx->subtitle_header); |
| av_bprint_init(&s->buffer, 0, AV_BPRINT_SIZE_UNLIMITED); |
| return s->ass_ctx ? 0 : AVERROR_INVALIDDATA; |
| } |
| |
| static void srt_text_cb(void *priv, const char *text, int len) |
| { |
| SRTContext *s = priv; |
| av_bprint_append_data(&s->buffer, text, len); |
| } |
| |
| static void srt_new_line_cb(void *priv, int forced) |
| { |
| srt_print(priv, "\r\n"); |
| } |
| |
| static void srt_style_cb(void *priv, char style, int close) |
| { |
| srt_stack_push_pop(priv, style, close); |
| if (!close) |
| srt_print(priv, "<%c>", style); |
| } |
| |
| static void srt_color_cb(void *priv, unsigned int color, unsigned int color_id) |
| { |
| if (color_id > 1) |
| return; |
| srt_stack_push_pop(priv, 'f', color == 0xFFFFFFFF); |
| if (color != 0xFFFFFFFF) |
| srt_print(priv, "<font color=\"#%06x\">", |
| (color & 0xFF0000) >> 16 | color & 0xFF00 | (color & 0xFF) << 16); |
| } |
| |
| static void srt_font_name_cb(void *priv, const char *name) |
| { |
| srt_stack_push_pop(priv, 'f', !name); |
| if (name) |
| srt_print(priv, "<font face=\"%s\">", name); |
| } |
| |
| static void srt_font_size_cb(void *priv, int size) |
| { |
| srt_stack_push_pop(priv, 'f', size < 0); |
| if (size >= 0) |
| srt_print(priv, "<font size=\"%d\">", size); |
| } |
| |
| static void srt_alignment_cb(void *priv, int alignment) |
| { |
| SRTContext *s = priv; |
| if (!s->alignment_applied && alignment >= 0) { |
| srt_print(s, "{\\an%d}", alignment); |
| s->alignment_applied = 1; |
| } |
| } |
| |
| static void srt_cancel_overrides_cb(void *priv, const char *style) |
| { |
| srt_stack_push_pop(priv, 0, 1); |
| srt_style_apply(priv, style); |
| } |
| |
| static void srt_move_cb(void *priv, int x1, int y1, int x2, int y2, |
| int t1, int t2) |
| { |
| // TODO: add a AV_PKT_DATA_SUBTITLE_POSITION side data when a new subtitles |
| // encoding API passing the AVPacket is available. |
| } |
| |
| static void srt_end_cb(void *priv) |
| { |
| srt_stack_push_pop(priv, 0, 1); |
| } |
| |
| static const ASSCodesCallbacks srt_callbacks = { |
| .text = srt_text_cb, |
| .new_line = srt_new_line_cb, |
| .style = srt_style_cb, |
| .color = srt_color_cb, |
| .font_name = srt_font_name_cb, |
| .font_size = srt_font_size_cb, |
| .alignment = srt_alignment_cb, |
| .cancel_overrides = srt_cancel_overrides_cb, |
| .move = srt_move_cb, |
| .end = srt_end_cb, |
| }; |
| |
| static const ASSCodesCallbacks text_callbacks = { |
| .text = srt_text_cb, |
| .new_line = srt_new_line_cb, |
| }; |
| |
| static int encode_frame(AVCodecContext *avctx, |
| unsigned char *buf, int bufsize, const AVSubtitle *sub, |
| const ASSCodesCallbacks *cb) |
| { |
| SRTContext *s = avctx->priv_data; |
| ASSDialog *dialog; |
| int i, num; |
| |
| av_bprint_clear(&s->buffer); |
| |
| for (i=0; i<sub->num_rects; i++) { |
| |
| if (sub->rects[i]->type != SUBTITLE_ASS) { |
| av_log(avctx, AV_LOG_ERROR, "Only SUBTITLE_ASS type supported.\n"); |
| return AVERROR(ENOSYS); |
| } |
| |
| dialog = ff_ass_split_dialog(s->ass_ctx, sub->rects[i]->ass, 0, &num); |
| for (; dialog && num--; dialog++) { |
| s->alignment_applied = 0; |
| srt_style_apply(s, dialog->style); |
| ff_ass_split_override_codes(cb, s, dialog->text); |
| } |
| } |
| |
| if (!av_bprint_is_complete(&s->buffer)) |
| return AVERROR(ENOMEM); |
| if (!s->buffer.len) |
| return 0; |
| |
| if (s->buffer.len > bufsize) { |
| av_log(avctx, AV_LOG_ERROR, "Buffer too small for ASS event.\n"); |
| return -1; |
| } |
| memcpy(buf, s->buffer.str, s->buffer.len); |
| |
| return s->buffer.len; |
| } |
| |
| static int srt_encode_frame(AVCodecContext *avctx, |
| unsigned char *buf, int bufsize, const AVSubtitle *sub) |
| { |
| return encode_frame(avctx, buf, bufsize, sub, &srt_callbacks); |
| } |
| |
| static int text_encode_frame(AVCodecContext *avctx, |
| unsigned char *buf, int bufsize, const AVSubtitle *sub) |
| { |
| return encode_frame(avctx, buf, bufsize, sub, &text_callbacks); |
| } |
| |
| static int srt_encode_close(AVCodecContext *avctx) |
| { |
| SRTContext *s = avctx->priv_data; |
| ff_ass_split_free(s->ass_ctx); |
| av_bprint_finalize(&s->buffer, NULL); |
| return 0; |
| } |
| |
| #if CONFIG_SRT_ENCODER |
| /* deprecated encoder */ |
| AVCodec ff_srt_encoder = { |
| .name = "srt", |
| .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"), |
| .type = AVMEDIA_TYPE_SUBTITLE, |
| .id = AV_CODEC_ID_SUBRIP, |
| .priv_data_size = sizeof(SRTContext), |
| .init = srt_encode_init, |
| .encode_sub = srt_encode_frame, |
| .close = srt_encode_close, |
| }; |
| #endif |
| |
| #if CONFIG_SUBRIP_ENCODER |
| AVCodec ff_subrip_encoder = { |
| .name = "subrip", |
| .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"), |
| .type = AVMEDIA_TYPE_SUBTITLE, |
| .id = AV_CODEC_ID_SUBRIP, |
| .priv_data_size = sizeof(SRTContext), |
| .init = srt_encode_init, |
| .encode_sub = srt_encode_frame, |
| .close = srt_encode_close, |
| }; |
| #endif |
| |
| #if CONFIG_TEXT_ENCODER |
| AVCodec ff_text_encoder = { |
| .name = "text", |
| .long_name = NULL_IF_CONFIG_SMALL("Raw text subtitle"), |
| .type = AVMEDIA_TYPE_SUBTITLE, |
| .id = AV_CODEC_ID_TEXT, |
| .priv_data_size = sizeof(SRTContext), |
| .init = srt_encode_init, |
| .encode_sub = text_encode_frame, |
| .close = srt_encode_close, |
| }; |
| #endif |
