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00029 #include <ass/ass.h>
00030
00031 #include "libavutil/avstring.h"
00032 #include "libavutil/imgutils.h"
00033 #include "libavutil/pixdesc.h"
00034 #include "drawutils.h"
00035 #include "avfilter.h"
00036
00037 typedef struct {
00038 ASS_Library *library;
00039 ASS_Renderer *renderer;
00040 ASS_Track *track;
00041 int hsub, vsub;
00042 char *filename;
00043 uint8_t rgba_map[4];
00044 int pix_step[4];
00045 } AssContext;
00046
00047
00048 int ass_libav_log_level_map[] = {
00049 AV_LOG_QUIET,
00050 AV_LOG_PANIC,
00051 AV_LOG_FATAL,
00052 AV_LOG_ERROR,
00053 AV_LOG_WARNING,
00054 AV_LOG_INFO,
00055 AV_LOG_VERBOSE,
00056 AV_LOG_DEBUG,
00057 };
00058
00059 static void ass_log(int ass_level, const char *fmt, va_list args, void *ctx)
00060 {
00061 int level = ass_libav_log_level_map[ass_level];
00062
00063 av_vlog(ctx, level, fmt, args);
00064 av_log(ctx, level, "\n");
00065 }
00066
00067 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
00068 {
00069 AssContext *ass = ctx->priv;
00070
00071 if (args)
00072 ass->filename = av_get_token(&args, ":");
00073 if (!ass->filename || !*ass->filename) {
00074 av_log(ctx, AV_LOG_ERROR, "No filename provided!\n");
00075 return AVERROR(EINVAL);
00076 }
00077
00078 ass->library = ass_library_init();
00079 if (!ass->library) {
00080 av_log(ctx, AV_LOG_ERROR, "Could not initialize libass.\n");
00081 return AVERROR(EINVAL);
00082 }
00083 ass_set_message_cb(ass->library, ass_log, ctx);
00084
00085 ass->renderer = ass_renderer_init(ass->library);
00086 if (!ass->renderer) {
00087 av_log(ctx, AV_LOG_ERROR, "Could not initialize libass renderer.\n");
00088 return AVERROR(EINVAL);
00089 }
00090
00091 ass->track = ass_read_file(ass->library, ass->filename, NULL);
00092 if (!ass->track) {
00093 av_log(ctx, AV_LOG_ERROR,
00094 "Could not create a libass track when reading file '%s'\n",
00095 ass->filename);
00096 return AVERROR(EINVAL);
00097 }
00098
00099 ass_set_fonts(ass->renderer, NULL, NULL, 1, NULL, 1);
00100
00101 return 0;
00102 }
00103
00104 static av_cold void uninit(AVFilterContext *ctx)
00105 {
00106 AssContext *ass = ctx->priv;
00107
00108 av_freep(&ass->filename);
00109 if (ass->track)
00110 ass_free_track(ass->track);
00111 if (ass->renderer)
00112 ass_renderer_done(ass->renderer);
00113 if (ass->library)
00114 ass_library_done(ass->library);
00115 }
00116
00117 static int query_formats(AVFilterContext *ctx)
00118 {
00119 static const enum PixelFormat pix_fmts[] = {
00120 PIX_FMT_ARGB, PIX_FMT_RGBA,
00121 PIX_FMT_ABGR, PIX_FMT_BGRA,
00122 PIX_FMT_RGB24, PIX_FMT_BGR24,
00123 PIX_FMT_NONE
00124 };
00125
00126 avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
00127
00128 return 0;
00129 }
00130
00131 static int config_input(AVFilterLink *inlink)
00132 {
00133 AssContext *ass = inlink->dst->priv;
00134 const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];
00135 double sar = inlink->sample_aspect_ratio.num ?
00136 av_q2d(inlink->sample_aspect_ratio) : 1;
00137 double dar = inlink->w / inlink->h * sar;
00138
00139 av_image_fill_max_pixsteps(ass->pix_step, NULL, pix_desc);
00140 ff_fill_rgba_map(ass->rgba_map, inlink->format);
00141
00142 ass->hsub = pix_desc->log2_chroma_w;
00143 ass->vsub = pix_desc->log2_chroma_h;
00144
00145 ass_set_frame_size (ass->renderer, inlink->w, inlink->h);
00146 ass_set_aspect_ratio(ass->renderer, dar, sar);
00147
00148 return 0;
00149 }
00150
00151 static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
00152
00153 #define R 0
00154 #define G 1
00155 #define B 2
00156 #define A 3
00157
00158 #define SET_PIXEL_RGB(picref, rgba_color, val, x, y, pixel_step, r_off, g_off, b_off) { \
00159 p = picref->data[0] + (x) * pixel_step + ((y) * picref->linesize[0]); \
00160 alpha = rgba_color[A] * (val) * 129; \
00161 *(p+r_off) = (alpha * rgba_color[R] + (255*255*129 - alpha) * *(p+r_off)) >> 23; \
00162 *(p+g_off) = (alpha * rgba_color[G] + (255*255*129 - alpha) * *(p+g_off)) >> 23; \
00163 *(p+b_off) = (alpha * rgba_color[B] + (255*255*129 - alpha) * *(p+b_off)) >> 23; \
00164 }
00165
00166
00167 #define AR(c) ( (c)>>24)
00168 #define AG(c) (((c)>>16)&0xFF)
00169 #define AB(c) (((c)>>8) &0xFF)
00170 #define AA(c) ((0xFF-c) &0xFF)
00171
00172 static void overlay_ass_image(AVFilterBufferRef *picref, const uint8_t *rgba_map, const int pix_step,
00173 const ASS_Image *image)
00174 {
00175 int i, j;
00176 int alpha;
00177 uint8_t *p;
00178 const int ro = rgba_map[R];
00179 const int go = rgba_map[G];
00180 const int bo = rgba_map[B];
00181
00182 for (; image; image = image->next) {
00183 uint8_t rgba_color[] = {AR(image->color), AG(image->color), AB(image->color), AA(image->color)};
00184 unsigned char *row = image->bitmap;
00185
00186 for (i = 0; i < image->h; i++) {
00187 for (j = 0; j < image->w; j++) {
00188 if (row[j]) {
00189 SET_PIXEL_RGB(picref, rgba_color, row[j], image->dst_x + j, image->dst_y + i, pix_step, ro, go, bo);
00190 }
00191 }
00192 row += image->stride;
00193 }
00194 }
00195 }
00196
00197 static void end_frame(AVFilterLink *inlink)
00198 {
00199 AVFilterContext *ctx = inlink->dst;
00200 AVFilterLink *outlink = ctx->outputs[0];
00201 AssContext *ass = ctx->priv;
00202 AVFilterBufferRef *picref = inlink->cur_buf;
00203 int detect_change = 0;
00204 double time_ms = picref->pts * av_q2d(inlink->time_base) * 1000;
00205 ASS_Image *image = ass_render_frame(ass->renderer, ass->track,
00206 time_ms, &detect_change);
00207
00208 if (detect_change)
00209 av_log(ctx, AV_LOG_DEBUG, "Change happened at time ms:%f\n", time_ms);
00210
00211 overlay_ass_image(picref, ass->rgba_map, ass->pix_step[0], image);
00212
00213 avfilter_draw_slice(outlink, 0, picref->video->h, 1);
00214 avfilter_end_frame(outlink);
00215 }
00216
00217 AVFilter avfilter_vf_ass = {
00218 .name = "ass",
00219 .description = NULL_IF_CONFIG_SMALL("Render subtitles onto input video using the libass library."),
00220 .priv_size = sizeof(AssContext),
00221 .init = init,
00222 .uninit = uninit,
00223 .query_formats = query_formats,
00224
00225 .inputs = (const AVFilterPad[]) {
00226 { .name = "default",
00227 .type = AVMEDIA_TYPE_VIDEO,
00228 .get_video_buffer = avfilter_null_get_video_buffer,
00229 .start_frame = avfilter_null_start_frame,
00230 .draw_slice = null_draw_slice,
00231 .end_frame = end_frame,
00232 .config_props = config_input,
00233 .min_perms = AV_PERM_WRITE | AV_PERM_READ,
00234 .rej_perms = AV_PERM_PRESERVE },
00235 { .name = NULL}
00236 },
00237 .outputs = (const AVFilterPad[]) {
00238 { .name = "default",
00239 .type = AVMEDIA_TYPE_VIDEO, },
00240 { .name = NULL}
00241 },
00242 };