1/*
2 * filter layer
3 * copyright (c) 2007 Bobby Bingham
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#include "libavcodec/imgconvert.h"
23#include "avfilter.h"
24
25unsigned avfilter_version(void) {
26    return LIBAVFILTER_VERSION_INT;
27}
28
29/** list of registered filters */
30struct FilterList
31{
32    AVFilter *filter;
33    struct FilterList *next;
34} *filters = NULL;
35
36/** helper macros to get the in/out pad on the dst/src filter */
37#define link_dpad(link)     link->dst-> input_pads[link->dstpad]
38#define link_spad(link)     link->src->output_pads[link->srcpad]
39
40AVFilterPicRef *avfilter_ref_pic(AVFilterPicRef *ref, int pmask)
41{
42    AVFilterPicRef *ret = av_malloc(sizeof(AVFilterPicRef));
43    *ret = *ref;
44    ret->perms &= pmask;
45    ret->pic->refcount ++;
46    return ret;
47}
48
49void avfilter_unref_pic(AVFilterPicRef *ref)
50{
51    if(!(--ref->pic->refcount))
52        ref->pic->free(ref->pic);
53    av_free(ref);
54}
55
56void avfilter_insert_pad(unsigned idx, unsigned *count, size_t padidx_off,
57                         AVFilterPad **pads, AVFilterLink ***links,
58                         AVFilterPad *newpad)
59{
60    unsigned i;
61
62    idx = FFMIN(idx, *count);
63
64    *pads  = av_realloc(*pads,  sizeof(AVFilterPad)   * (*count + 1));
65    *links = av_realloc(*links, sizeof(AVFilterLink*) * (*count + 1));
66    memmove(*pads +idx+1, *pads +idx, sizeof(AVFilterPad)   * (*count-idx));
67    memmove(*links+idx+1, *links+idx, sizeof(AVFilterLink*) * (*count-idx));
68    memcpy(*pads+idx, newpad, sizeof(AVFilterPad));
69    (*links)[idx] = NULL;
70
71    (*count) ++;
72    for(i = idx+1; i < *count; i ++)
73        if(*links[i])
74            (*(unsigned *)((uint8_t *) *links[i] + padidx_off)) ++;
75}
76
77int avfilter_link(AVFilterContext *src, unsigned srcpad,
78                  AVFilterContext *dst, unsigned dstpad)
79{
80    AVFilterLink *link;
81
82    if(src->output_count <= srcpad || dst->input_count <= dstpad ||
83       src->outputs[srcpad]        || dst->inputs[dstpad])
84        return -1;
85
86    src->outputs[srcpad] =
87    dst-> inputs[dstpad] = link = av_mallocz(sizeof(AVFilterLink));
88
89    link->src     = src;
90    link->dst     = dst;
91    link->srcpad  = srcpad;
92    link->dstpad  = dstpad;
93    link->format  = PIX_FMT_NONE;
94
95    return 0;
96}
97
98int avfilter_insert_filter(AVFilterLink *link, AVFilterContext *filt,
99                           unsigned in, unsigned out)
100{
101    av_log(link->dst, AV_LOG_INFO, "auto-inserting filter '%s'\n",
102            filt->filter->name);
103
104    link->dst->inputs[link->dstpad] = NULL;
105    if(avfilter_link(filt, out, link->dst, link->dstpad)) {
106        /* failed to link output filter to new filter */
107        link->dst->inputs[link->dstpad] = link;
108        return -1;
109    }
110
111    /* re-hookup the link to the new destination filter we inserted */
112    link->dst = filt;
113    link->dstpad = in;
114    filt->inputs[in] = link;
115
116    /* if any information on supported colorspaces already exists on the
117     * link, we need to preserve that */
118    if(link->out_formats)
119        avfilter_formats_changeref(&link->out_formats,
120                                   &filt->outputs[out]->out_formats);
121
122    return 0;
123}
124
125int avfilter_config_links(AVFilterContext *filter)
126{
127    int (*config_link)(AVFilterLink *);
128    unsigned i;
129
130    for(i = 0; i < filter->input_count; i ++) {
131        AVFilterLink *link = filter->inputs[i];
132
133        if(!link) continue;
134
135        switch(link->init_state) {
136        case AVLINK_INIT:
137            continue;
138        case AVLINK_STARTINIT:
139            av_log(filter, AV_LOG_INFO, "circular filter chain detected\n");
140            return 0;
141        case AVLINK_UNINIT:
142            link->init_state = AVLINK_STARTINIT;
143
144            if(avfilter_config_links(link->src))
145                return -1;
146
147            if(!(config_link = link_spad(link).config_props))
148                config_link  = avfilter_default_config_output_link;
149            if(config_link(link))
150                return -1;
151
152            if((config_link = link_dpad(link).config_props))
153                if(config_link(link))
154                    return -1;
155
156            link->init_state = AVLINK_INIT;
157        }
158    }
159
160    return 0;
161}
162
163AVFilterPicRef *avfilter_get_video_buffer(AVFilterLink *link, int perms)
164{
165    AVFilterPicRef *ret = NULL;
166
167    if(link_dpad(link).get_video_buffer)
168        ret = link_dpad(link).get_video_buffer(link, perms);
169
170    if(!ret)
171        ret = avfilter_default_get_video_buffer(link, perms);
172
173    return ret;
174}
175
176int avfilter_request_frame(AVFilterLink *link)
177{
178    if(link_spad(link).request_frame)
179        return link_spad(link).request_frame(link);
180    else if(link->src->inputs[0])
181        return avfilter_request_frame(link->src->inputs[0]);
182    else return -1;
183}
184
185int avfilter_poll_frame(AVFilterLink *link)
186{
187    int i, min=INT_MAX;
188
189    if(link_spad(link).poll_frame)
190        return link_spad(link).poll_frame(link);
191
192    for (i=0; i<link->src->input_count; i++) {
193        if(!link->src->inputs[i])
194            return -1;
195        min = FFMIN(min, avfilter_poll_frame(link->src->inputs[i]));
196    }
197
198    return min;
199}
200
201/* XXX: should we do the duplicating of the picture ref here, instead of
202 * forcing the source filter to do it? */
203void avfilter_start_frame(AVFilterLink *link, AVFilterPicRef *picref)
204{
205    void (*start_frame)(AVFilterLink *, AVFilterPicRef *);
206    AVFilterPad *dst = &link_dpad(link);
207
208    if(!(start_frame = dst->start_frame))
209        start_frame = avfilter_default_start_frame;
210
211    /* prepare to copy the picture if it has insufficient permissions */
212    if((dst->min_perms & picref->perms) != dst->min_perms ||
213        dst->rej_perms & picref->perms) {
214        /*
215        av_log(link->dst, AV_LOG_INFO,
216                "frame copy needed (have perms %x, need %x, reject %x)\n",
217                picref->perms,
218                link_dpad(link).min_perms, link_dpad(link).rej_perms);
219        */
220
221        link->cur_pic = avfilter_default_get_video_buffer(link, dst->min_perms);
222        link->srcpic = picref;
223        link->cur_pic->pts = link->srcpic->pts;
224    }
225    else
226        link->cur_pic = picref;
227
228    start_frame(link, link->cur_pic);
229}
230
231void avfilter_end_frame(AVFilterLink *link)
232{
233    void (*end_frame)(AVFilterLink *);
234
235    if(!(end_frame = link_dpad(link).end_frame))
236        end_frame = avfilter_default_end_frame;
237
238    end_frame(link);
239
240    /* unreference the source picture if we're feeding the destination filter
241     * a copied version dues to permission issues */
242    if(link->srcpic) {
243        avfilter_unref_pic(link->srcpic);
244        link->srcpic = NULL;
245    }
246
247}
248
249void avfilter_draw_slice(AVFilterLink *link, int y, int h)
250{
251    uint8_t *src[4], *dst[4];
252    int i, j, hsub, vsub;
253    void (*draw_slice)(AVFilterLink *, int, int);
254
255    /* copy the slice if needed for permission reasons */
256    if(link->srcpic) {
257        avcodec_get_chroma_sub_sample(link->format, &hsub, &vsub);
258
259        for(i = 0; i < 4; i ++) {
260            if(link->srcpic->data[i]) {
261                src[i] = link->srcpic-> data[i] +
262                    (y >> (i==0 ? 0 : vsub)) * link->srcpic-> linesize[i];
263                dst[i] = link->cur_pic->data[i] +
264                    (y >> (i==0 ? 0 : vsub)) * link->cur_pic->linesize[i];
265            } else
266                src[i] = dst[i] = NULL;
267        }
268
269        for(i = 0; i < 4; i ++) {
270            int planew =
271                ff_get_plane_bytewidth(link->format, link->cur_pic->w, i);
272
273            if(!src[i]) continue;
274
275            for(j = 0; j < h >> (i==0 ? 0 : vsub); j ++) {
276                memcpy(dst[i], src[i], planew);
277                src[i] += link->srcpic ->linesize[i];
278                dst[i] += link->cur_pic->linesize[i];
279            }
280        }
281    }
282
283    if(!(draw_slice = link_dpad(link).draw_slice))
284        draw_slice = avfilter_default_draw_slice;
285    draw_slice(link, y, h);
286}
287
288AVFilter *avfilter_get_by_name(const char *name)
289{
290    struct FilterList *filt;
291
292    for(filt = filters; filt; filt = filt->next)
293        if(!strcmp(filt->filter->name, name))
294            return filt->filter;
295
296    return NULL;
297}
298
299void avfilter_register(AVFilter *filter)
300{
301    struct FilterList *newfilt = av_malloc(sizeof(struct FilterList));
302
303    newfilt->filter = filter;
304    newfilt->next   = filters;
305    filters         = newfilt;
306}
307
308void avfilter_uninit(void)
309{
310    struct FilterList *tmp;
311
312    for(; filters; filters = tmp) {
313        tmp = filters->next;
314        av_free(filters);
315    }
316}
317
318static int pad_count(const AVFilterPad *pads)
319{
320    int count;
321
322    for(count = 0; pads->name; count ++) pads ++;
323    return count;
324}
325
326static const char *filter_name(void *p)
327{
328    AVFilterContext *filter = p;
329    return filter->filter->name;
330}
331
332static const AVClass avfilter_class = {
333    "AVFilter",
334    filter_name
335};
336
337AVFilterContext *avfilter_open(AVFilter *filter, const char *inst_name)
338{
339    AVFilterContext *ret;
340
341    if (!filter)
342        return 0;
343
344    ret = av_mallocz(sizeof(AVFilterContext));
345
346    ret->av_class = &avfilter_class;
347    ret->filter   = filter;
348    ret->name     = inst_name ? av_strdup(inst_name) : NULL;
349    ret->priv     = av_mallocz(filter->priv_size);
350
351    ret->input_count  = pad_count(filter->inputs);
352    if (ret->input_count) {
353        ret->input_pads   = av_malloc(sizeof(AVFilterPad) * ret->input_count);
354        memcpy(ret->input_pads, filter->inputs, sizeof(AVFilterPad) * ret->input_count);
355        ret->inputs       = av_mallocz(sizeof(AVFilterLink*) * ret->input_count);
356    }
357
358    ret->output_count = pad_count(filter->outputs);
359    if (ret->output_count) {
360        ret->output_pads  = av_malloc(sizeof(AVFilterPad) * ret->output_count);
361        memcpy(ret->output_pads, filter->outputs, sizeof(AVFilterPad) * ret->output_count);
362        ret->outputs      = av_mallocz(sizeof(AVFilterLink*) * ret->output_count);
363    }
364
365    return ret;
366}
367
368void avfilter_destroy(AVFilterContext *filter)
369{
370    int i;
371
372    if(filter->filter->uninit)
373        filter->filter->uninit(filter);
374
375    for(i = 0; i < filter->input_count; i ++) {
376        if(filter->inputs[i])
377            filter->inputs[i]->src->outputs[filter->inputs[i]->srcpad] = NULL;
378        av_freep(&filter->inputs[i]);
379    }
380    for(i = 0; i < filter->output_count; i ++) {
381        if(filter->outputs[i])
382            filter->outputs[i]->dst->inputs[filter->outputs[i]->dstpad] = NULL;
383        av_freep(&filter->outputs[i]);
384    }
385
386    av_freep(&filter->name);
387    av_freep(&filter->input_pads);
388    av_freep(&filter->output_pads);
389    av_freep(&filter->inputs);
390    av_freep(&filter->outputs);
391    av_freep(&filter->priv);
392    av_free(filter);
393}
394
395int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque)
396{
397    int ret=0;
398
399    if(filter->filter->init)
400        ret = filter->filter->init(filter, args, opaque);
401    return ret;
402}
403
404