/* * ARIB STD-B24 caption decoder using the libaribb24 library * Copyright (c) 2019 Jan Ekström * * 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 "libavcodec/ass.h" #include "libavutil/log.h" #include "libavutil/opt.h" #include <aribb24/aribb24.h> #include <aribb24/parser.h> #include <aribb24/decoder.h> typedef struct Libaribb24Context { AVClass *class; arib_instance_t *lib_instance; arib_parser_t *parser; arib_decoder_t *decoder; int read_order; char *aribb24_base_path; unsigned int aribb24_skip_ruby; } Libaribb24Context; static unsigned int get_profile_font_size(int profile) { switch (profile) { case FF_PROFILE_ARIB_PROFILE_A: return 36; case FF_PROFILE_ARIB_PROFILE_C: return 18; default: return 0; } } static void libaribb24_log(void *p, const char *msg) { av_log((AVCodecContext *)p, AV_LOG_INFO, "%s\n", msg); } static int libaribb24_generate_ass_header(AVCodecContext *avctx) { unsigned int plane_width = 0; unsigned int plane_height = 0; unsigned int font_size = 0; switch (avctx->profile) { case FF_PROFILE_ARIB_PROFILE_A: plane_width = 960; plane_height = 540; font_size = get_profile_font_size(avctx->profile); break; case FF_PROFILE_ARIB_PROFILE_C: plane_width = 320; plane_height = 180; font_size = get_profile_font_size(avctx->profile); break; default: av_log(avctx, AV_LOG_ERROR, "Unknown or unsupported profile set!\n"); return AVERROR(EINVAL); } avctx->subtitle_header = av_asprintf( "[Script Info]\r\n" "; Script generated by FFmpeg/Lavc%s\r\n" "ScriptType: v4.00+\r\n" "PlayResX: %d\r\n" "PlayResY: %d\r\n" "\r\n" "[V4+ Styles]\r\n" /* ASSv4 header */ "Format: Name, " "Fontname, Fontsize, " "PrimaryColour, SecondaryColour, OutlineColour, BackColour, " "Bold, Italic, Underline, StrikeOut, " "ScaleX, ScaleY, " "Spacing, Angle, " "BorderStyle, Outline, Shadow, " "Alignment, MarginL, MarginR, MarginV, " "Encoding\r\n" "Style: " "Default," /* Name */ "%s,%d," /* Font{name,size} */ "&H%x,&H%x,&H%x,&H%x," /* {Primary,Secondary,Outline,Back}Colour */ "%d,%d,%d,0," /* Bold, Italic, Underline, StrikeOut */ "100,100," /* Scale{X,Y} */ "0,0," /* Spacing, Angle */ "%d,1,0," /* BorderStyle, Outline, Shadow */ "%d,10,10,10," /* Alignment, Margin[LRV] */ "0\r\n" /* Encoding */ "\r\n" "[Events]\r\n" "Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text\r\n", !(avctx->flags & AV_CODEC_FLAG_BITEXACT) ? AV_STRINGIFY(LIBAVCODEC_VERSION) : "", plane_width, plane_height, ASS_DEFAULT_FONT, font_size, ASS_DEFAULT_COLOR, ASS_DEFAULT_COLOR, ASS_DEFAULT_BACK_COLOR, ASS_DEFAULT_BACK_COLOR, -ASS_DEFAULT_BOLD, -ASS_DEFAULT_ITALIC, -ASS_DEFAULT_UNDERLINE, ASS_DEFAULT_BORDERSTYLE, ASS_DEFAULT_ALIGNMENT); if (!avctx->subtitle_header) return AVERROR(ENOMEM); avctx->subtitle_header_size = strlen(avctx->subtitle_header); return 0; } static int libaribb24_init(AVCodecContext *avctx) { Libaribb24Context *b24 = avctx->priv_data; void(* arib_dec_init)(arib_decoder_t* decoder) = NULL; int ret_code = AVERROR_EXTERNAL; if (!(b24->lib_instance = arib_instance_new(avctx))) { av_log(avctx, AV_LOG_ERROR, "Failed to initialize libaribb24!\n"); goto init_fail; } if (b24->aribb24_base_path) { av_log(avctx, AV_LOG_INFO, "Setting the libaribb24 base path to '%s'\n", b24->aribb24_base_path); arib_set_base_path(b24->lib_instance, b24->aribb24_base_path); } arib_register_messages_callback(b24->lib_instance, libaribb24_log); if (!(b24->parser = arib_get_parser(b24->lib_instance))) { av_log(avctx, AV_LOG_ERROR, "Failed to initialize libaribb24 PES parser!\n"); goto init_fail; } if (!(b24->decoder = arib_get_decoder(b24->lib_instance))) { av_log(avctx, AV_LOG_ERROR, "Failed to initialize libaribb24 decoder!\n"); goto init_fail; } switch (avctx->profile) { case FF_PROFILE_ARIB_PROFILE_A: arib_dec_init = arib_initialize_decoder_a_profile; break; case FF_PROFILE_ARIB_PROFILE_C: arib_dec_init = arib_initialize_decoder_c_profile; break; default: av_log(avctx, AV_LOG_ERROR, "Unknown or unsupported profile set!\n"); ret_code = AVERROR(EINVAL); goto init_fail; } arib_dec_init(b24->decoder); if (libaribb24_generate_ass_header(avctx) < 0) { ret_code = AVERROR(ENOMEM); goto init_fail; } return 0; init_fail: if (b24->decoder) arib_finalize_decoder(b24->decoder); if (b24->lib_instance) arib_instance_destroy(b24->lib_instance); return ret_code; } static int libaribb24_close(AVCodecContext *avctx) { Libaribb24Context *b24 = avctx->priv_data; if (b24->decoder) arib_finalize_decoder(b24->decoder); if (b24->lib_instance) arib_instance_destroy(b24->lib_instance); return 0; } #define RGB_TO_BGR(c) (((c) & 0xff) << 16 | ((c) & 0xff00) | (((c) >> 16) & 0xff)) static int libaribb24_handle_regions(AVCodecContext *avctx, AVSubtitle *sub) { Libaribb24Context *b24 = avctx->priv_data; const arib_buf_region_t *region = arib_decoder_get_regions(b24->decoder); unsigned int profile_font_size = get_profile_font_size(avctx->profile); AVBPrint buf = { 0 }; int ret = 0; av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED); while (region) { ptrdiff_t region_length = region->p_end - region->p_start; unsigned int ruby_region = region->i_fontheight == (profile_font_size / 2); // ASS requires us to make the colors BGR, so we convert here int foreground_bgr_color = RGB_TO_BGR(region->i_foreground_color); int background_bgr_color = RGB_TO_BGR(region->i_background_color); if (region_length < 0) { av_log(avctx, AV_LOG_ERROR, "Invalid negative region length!\n"); ret = AVERROR_INVALIDDATA; break; } if (region_length == 0 || (ruby_region && b24->aribb24_skip_ruby)) { goto next_region; } // color and alpha if (foreground_bgr_color != ASS_DEFAULT_COLOR) av_bprintf(&buf, "{\\1c&H%06x&}", foreground_bgr_color); if (region->i_foreground_alpha != 0) av_bprintf(&buf, "{\\1a&H%02x&}", region->i_foreground_alpha); if (background_bgr_color != ASS_DEFAULT_BACK_COLOR) av_bprintf(&buf, "{\\3c&H%06x&}", background_bgr_color); if (region->i_background_alpha != 0) av_bprintf(&buf, "{\\3a&H%02x&}", region->i_background_alpha); // font size if (region->i_fontwidth != profile_font_size || region->i_fontheight != profile_font_size) { av_bprintf(&buf, "{\\fscx%"PRId64"\\fscy%"PRId64"}", av_rescale(region->i_fontwidth, 100, profile_font_size), av_rescale(region->i_fontheight, 100, profile_font_size)); } // TODO: positioning av_bprint_append_data(&buf, region->p_start, region_length); av_bprintf(&buf, "{\\r}"); next_region: region = region->p_next; } if (!av_bprint_is_complete(&buf)) ret = AVERROR(ENOMEM); if (ret == 0) { av_log(avctx, AV_LOG_DEBUG, "Styled ASS line: %s\n", buf.str); ret = ff_ass_add_rect(sub, buf.str, b24->read_order++, 0, NULL, NULL); } av_bprint_finalize(&buf, NULL); return ret; } static int libaribb24_decode(AVCodecContext *avctx, void *data, int *got_sub_ptr, AVPacket *pkt) { Libaribb24Context *b24 = avctx->priv_data; AVSubtitle *sub = data; size_t parsed_data_size = 0; size_t decoded_subtitle_size = 0; const unsigned char *parsed_data = NULL; char *decoded_subtitle = NULL; time_t subtitle_duration = 0; int ret = 0; if (pkt->size <= 0) return pkt->size; arib_parse_pes(b24->parser, pkt->data, pkt->size); parsed_data = arib_parser_get_data(b24->parser, &parsed_data_size); if (!parsed_data || !parsed_data_size) { av_log(avctx, AV_LOG_DEBUG, "No decode'able data was received from " "packet (dts: %"PRId64", pts: %"PRId64").\n", pkt->dts, pkt->pts); return pkt->size; } decoded_subtitle_size = parsed_data_size * 4; if (!(decoded_subtitle = av_mallocz(decoded_subtitle_size + 1))) { av_log(avctx, AV_LOG_ERROR, "Failed to allocate buffer for decoded subtitle!\n"); return AVERROR(ENOMEM); } decoded_subtitle_size = arib_decode_buffer(b24->decoder, parsed_data, parsed_data_size, decoded_subtitle, decoded_subtitle_size); subtitle_duration = arib_decoder_get_time(b24->decoder); if (avctx->pkt_timebase.num && pkt->pts != AV_NOPTS_VALUE) sub->pts = av_rescale_q(pkt->pts, avctx->pkt_timebase, AV_TIME_BASE_Q); sub->end_display_time = subtitle_duration ? av_rescale_q(subtitle_duration, AV_TIME_BASE_Q, (AVRational){1, 1000}) : UINT32_MAX; av_log(avctx, AV_LOG_DEBUG, "Result: '%s' (size: %zu, pkt_pts: %"PRId64", sub_pts: %"PRId64" " "duration: %"PRIu32", pkt_timebase: %d/%d, time_base: %d/%d')\n", decoded_subtitle ? decoded_subtitle : "<no subtitle>", decoded_subtitle_size, pkt->pts, sub->pts, sub->end_display_time, avctx->pkt_timebase.num, avctx->pkt_timebase.den, avctx->time_base.num, avctx->time_base.den); if (decoded_subtitle) ret = libaribb24_handle_regions(avctx, sub); *got_sub_ptr = sub->num_rects > 0; av_free(decoded_subtitle); // flush the region buffers, otherwise the linked list keeps getting // longer and longer... arib_finalize_decoder(b24->decoder); return ret < 0 ? ret : pkt->size; } static void libaribb24_flush(AVCodecContext *avctx) { Libaribb24Context *b24 = avctx->priv_data; if (!(avctx->flags2 & AV_CODEC_FLAG2_RO_FLUSH_NOOP)) b24->read_order = 0; } #define OFFSET(x) offsetof(Libaribb24Context, x) #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM static const AVOption options[] = { { "aribb24-base-path", "set the base path for the libaribb24 library", OFFSET(aribb24_base_path), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD }, { "aribb24-skip-ruby-text", "skip ruby text blocks during decoding", OFFSET(aribb24_skip_ruby), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, SD }, { NULL } }; static const AVClass aribb24_class = { .class_name = "libaribb24 decoder", .item_name = av_default_item_name, .option = options, .version = LIBAVUTIL_VERSION_INT, }; const AVCodec ff_libaribb24_decoder = { .name = "libaribb24", .long_name = NULL_IF_CONFIG_SMALL("libaribb24 ARIB STD-B24 caption decoder"), .type = AVMEDIA_TYPE_SUBTITLE, .id = AV_CODEC_ID_ARIB_CAPTION, .priv_data_size = sizeof(Libaribb24Context), .init = libaribb24_init, .close = libaribb24_close, .decode = libaribb24_decode, .flush = libaribb24_flush, .priv_class= &aribb24_class, .wrapper_name = "libaribb24", };