@@ -20,6 +20,7 @@ version 10:

 - avconv -deinterlace option removed, the yadif filter should be used instead

 - Apple Intermediate Codec decoder

 - Escape 130 video decoder

+- support for slice multithreading in libavfilter

 version 9:

@@ -1284,6 +1284,9 @@ static void show_help_filter(const char *name)

     printf("Filter %s [%s]:\n", f->name, f->description);

+    if (f->flags & AVFILTER_FLAG_SLICE_THREADS)

+        printf("    slice threading supported\n");

+

     printf("    Inputs:\n");

     count = avfilter_pad_count(f->inputs);

     for (i = 0; i < count; i++) {

@@ -13,6 +13,13 @@ libavutil:     2012-10-22

 API changes, most recent first:

+2013-05-xx - xxxxxxx - lavfi 3.10.0 - avfilter.h

+  Add support for slice multithreading to lavfi. Filters supporting threading

+  are marked with AVFILTER_FLAG_SLICE_THREADS.

+  New fields AVFilterContext.thread_type, AVFilterGraph.thread_type and

+  AVFilterGraph.nb_threads (accessible directly or through AVOptions) may be

+  used to configure multithreading.

+

 2013-xx-xx - xxxxxxx - lavu 52.12.0 - cpu.h

   Add av_cpu_count() function for getting the number of logical CPUs.

@@ -92,5 +92,7 @@ OBJS-$(CONFIG_TESTSRC_FILTER)                += vsrc_testsrc.o

 OBJS-$(CONFIG_NULLSINK_FILTER)               += vsink_nullsink.o

+OBJS-$(HAVE_THREADS)                         += pthread.o

+

 TOOLS     = graph2dot

 TESTPROGS = filtfmts

@@ -352,14 +352,37 @@ static const AVClass *filter_child_class_next(const AVClass *prev)

     return NULL;

 }

+#define OFFSET(x) offsetof(AVFilterContext, x)

+#define FLAGS AV_OPT_FLAG_VIDEO_PARAM

+static const AVOption options[] = {

+    { "thread_type", "Allowed thread types", OFFSET(thread_type), AV_OPT_TYPE_FLAGS,

+        { .i64 = AVFILTER_THREAD_SLICE }, 0, INT_MAX, FLAGS, "thread_type" },

+        { "slice", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AVFILTER_THREAD_SLICE }, .unit = "thread_type" },

+    { NULL },

+};

+

 static const AVClass avfilter_class = {

     .class_name = "AVFilter",

     .item_name  = filter_name,

     .version    = LIBAVUTIL_VERSION_INT,

     .child_next = filter_child_next,

     .child_class_next = filter_child_class_next,

+    .option           = options,

 };

+static int default_execute(AVFilterContext *ctx, action_func *func, void *arg,

+                           int *ret, int nb_jobs)

+{

+    int i;

+

+    for (i = 0; i < nb_jobs; i++) {

+        int r = func(ctx, arg, i, nb_jobs);

+        if (ret)

+            ret[i] = r;

+    }

+    return 0;

+}

+

 AVFilterContext *ff_filter_alloc(const AVFilter *filter, const char *inst_name)

 {

     AVFilterContext *ret;

@@ -380,11 +403,17 @@ AVFilterContext *ff_filter_alloc(const AVFilter *filter, const char *inst_name)

             goto err;

     }

+    av_opt_set_defaults(ret);

     if (filter->priv_class) {

         *(const AVClass**)ret->priv = filter->priv_class;

         av_opt_set_defaults(ret->priv);

     }

+    ret->internal = av_mallocz(sizeof(*ret->internal));

+    if (!ret->internal)

+        goto err;

+    ret->internal->execute = default_execute;

+

     ret->nb_inputs = avfilter_pad_count(filter->inputs);

     if (ret->nb_inputs ) {

         ret->input_pads   = av_malloc(sizeof(AVFilterPad) * ret->nb_inputs);

@@ -421,6 +450,7 @@ err:

     av_freep(&ret->output_pads);

     ret->nb_outputs = 0;

     av_freep(&ret->priv);

+    av_freep(&ret->internal);

     av_free(ret);

     return NULL;

 }

@@ -478,6 +508,7 @@ void avfilter_free(AVFilterContext *filter)

     av_freep(&filter->inputs);

     av_freep(&filter->outputs);

     av_freep(&filter->priv);

+    av_freep(&filter->internal);

     av_free(filter);

 }

@@ -525,6 +556,21 @@ int avfilter_init_dict(AVFilterContext *ctx, AVDictionary **options)

 {

     int ret = 0;

+    ret = av_opt_set_dict(ctx, options);

+    if (ret < 0) {

+        av_log(ctx, AV_LOG_ERROR, "Error applying generic filter options.\n");

+        return ret;

+    }

+

+    if (ctx->filter->flags & AVFILTER_FLAG_SLICE_THREADS &&

+        ctx->thread_type & ctx->graph->thread_type & AVFILTER_THREAD_SLICE &&

+        ctx->graph->internal->thread_execute) {

+        ctx->thread_type       = AVFILTER_THREAD_SLICE;

+        ctx->internal->execute = ctx->graph->internal->thread_execute;

+    } else {

+        ctx->thread_type = 0;

+    }

+

     if (ctx->filter->priv_class) {

         ret = av_opt_set_dict(ctx->priv, options);

         if (ret < 0) {

@@ -401,6 +401,11 @@ enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx);

  * the options supplied to it.

  */

 #define AVFILTER_FLAG_DYNAMIC_OUTPUTS       (1 << 1)

+/**

+ * The filter supports multithreading by splitting frames into multiple parts

+ * and processing them concurrently.

+ */

+#define AVFILTER_FLAG_SLICE_THREADS         (1 << 2)

 /**

  * Filter definition. This defines the pads a filter contains, and all the

@@ -472,6 +477,13 @@ typedef struct AVFilter {

     struct AVFilter *next;

 } AVFilter;

+/**

+ * Process multiple parts of the frame concurrently.

+ */

+#define AVFILTER_THREAD_SLICE (1 << 0)

+

+typedef struct AVFilterInternal AVFilterInternal;

+

 /** An instance of a filter */

 struct AVFilterContext {

     const AVClass *av_class;              ///< needed for av_log()

@@ -497,6 +509,29 @@ struct AVFilterContext {

     void *priv;                     ///< private data for use by the filter

     struct AVFilterGraph *graph;    ///< filtergraph this filter belongs to

+

+    /**

+     * Type of multithreading being allowed/used. A combination of

+     * AVFILTER_THREAD_* flags.

+     *

+     * May be set by the caller before initializing the filter to forbid some

+     * or all kinds of multithreading for this filter. The default is allowing

+     * everything.

+     *

+     * When the filter is initialized, this field is combined using bit AND with

+     * AVFilterGraph.thread_type to get the final mask used for determining

+     * allowed threading types. I.e. a threading type needs to be set in both

+     * to be allowed.

+     *

+     * After the filter is initialzed, libavfilter sets this field to the

+     * threading type that is actually used (0 for no multithreading).

+     */

+    int thread_type;

+

+    /**

+     * An opaque struct for libavfilter internal use.

+     */

+    AVFilterInternal *internal;

 };

 /**

@@ -793,6 +828,8 @@ int avfilter_copy_buf_props(AVFrame *dst, const AVFilterBufferRef *src);

  */

 const AVClass *avfilter_get_class(void);

+typedef struct AVFilterGraphInternal AVFilterGraphInternal;

+

 typedef struct AVFilterGraph {

     const AVClass *av_class;

 #if FF_API_FOO_COUNT

@@ -809,6 +846,32 @@ typedef struct AVFilterGraph {

 #if FF_API_FOO_COUNT

     unsigned nb_filters;

 #endif

+

+    /**

+     * Type of multithreading allowed for filters in this graph. A combination

+     * of AVFILTER_THREAD_* flags.

+     *

+     * May be set by the caller at any point, the setting will apply to all

+     * filters initialized after that. The default is allowing everything.

+     *

+     * When a filter in this graph is initialized, this field is combined using

+     * bit AND with AVFilterContext.thread_type to get the final mask used for

+     * determining allowed threading types. I.e. a threading type needs to be

+     * set in both to be allowed.

+     */

+    int thread_type;

+

+    /**

+     * Maximum number of threads used by filters in this graph. May be set by

+     * the caller before adding any filters to the filtergraph. Zero (the

+     * default) means that the number of threads is determined automatically.

+     */

+    int nb_threads;

+

+    /**

+     * Opaque object for libavfilter internal use.

+     */

+    AVFilterGraphInternal *internal;

 } AVFilterGraph;

 /**

@@ -20,6 +20,8 @@

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  */

+#include "config.h"

+

 #include <string.h>

 #include "libavutil/avassert.h"

@@ -27,22 +29,59 @@

 #include "libavutil/channel_layout.h"

 #include "libavutil/common.h"

 #include "libavutil/log.h"

+#include "libavutil/opt.h"

+

 #include "avfilter.h"

 #include "formats.h"

 #include "internal.h"

+#include "thread.h"

+

+#define OFFSET(x) offsetof(AVFilterGraph, x)

+#define FLAGS AV_OPT_FLAG_VIDEO_PARAM

+static const AVOption filtergraph_options[] = {

+    { "thread_type", "Allowed thread types", OFFSET(thread_type), AV_OPT_TYPE_FLAGS,

+        { .i64 = AVFILTER_THREAD_SLICE }, 0, INT_MAX, FLAGS, "thread_type" },

+        { "slice", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = AVFILTER_THREAD_SLICE }, .flags = FLAGS, .unit = "thread_type" },

+    { "threads",     "Maximum number of threads", OFFSET(nb_threads),

+        AV_OPT_TYPE_INT,   { .i64 = 0 }, 0, INT_MAX, FLAGS },

+    { NULL },

+};

 static const AVClass filtergraph_class = {

     .class_name = "AVFilterGraph",

     .item_name  = av_default_item_name,

     .version    = LIBAVUTIL_VERSION_INT,

+    .option     = filtergraph_options,

 };

+#if !HAVE_THREADS

+void ff_graph_thread_free(AVFilterGraph *graph)

+{

+}

+

+int ff_graph_thread_init(AVFilterGraph *graph)

+{

+    graph->thread_type = 0;

+    graph->nb_threads  = 1;

+    return 0;

+}

+#endif

+

 AVFilterGraph *avfilter_graph_alloc(void)

 {

     AVFilterGraph *ret = av_mallocz(sizeof(*ret));

     if (!ret)

         return NULL;

+

+    ret->internal = av_mallocz(sizeof(*ret->internal));

+    if (!ret->internal) {

+        av_freep(&ret);

+        return NULL;

+    }

+

     ret->av_class = &filtergraph_class;

+    av_opt_set_defaults(ret);

+

     return ret;

 }

@@ -67,9 +106,12 @@ void avfilter_graph_free(AVFilterGraph **graph)

     while ((*graph)->nb_filters)

         avfilter_free((*graph)->filters[0]);

+    ff_graph_thread_free(*graph);

+

     av_freep(&(*graph)->scale_sws_opts);

     av_freep(&(*graph)->resample_lavr_opts);

     av_freep(&(*graph)->filters);

+    av_freep(&(*graph)->internal);

     av_freep(graph);

 }

@@ -123,6 +165,14 @@ AVFilterContext *avfilter_graph_alloc_filter(AVFilterGraph *graph,

 {

     AVFilterContext **filters, *s;

+    if (graph->thread_type && !graph->internal->thread) {

+        int ret = ff_graph_thread_init(graph);

+        if (ret < 0) {

+            av_log(graph, AV_LOG_ERROR, "Error initializing threading.\n");

+            return NULL;

+        }

+    }

+

     s = ff_filter_alloc(filter, name);

     if (!s)

         return NULL;

@@ -25,6 +25,7 @@

  */

 #include "avfilter.h"

+#include "thread.h"

 #if !FF_API_AVFILTERPAD_PUBLIC

 /**

@@ -117,6 +118,17 @@ struct AVFilterPad {

 };

 #endif

+struct AVFilterGraphInternal {

+    void *thread;

+    int (*thread_execute)(AVFilterContext *ctx, action_func *func, void *arg,

+                          int *ret, int nb_jobs);

+};

+

+struct AVFilterInternal {

+    int (*execute)(AVFilterContext *ctx, action_func *func, void *arg,

+                   int *ret, int nb_jobs);

+};

+

 /** default handler for freeing audio/video buffer when there are no references left */

 void ff_avfilter_default_free_buffer(AVFilterBuffer *buf);

new file mode 100644

@@ -0,0 +1,229 @@

+/*

+ *

+ * This file is part of Libav.

+ *

+ * Libav 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.

+ *

+ * Libav 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 Libav; if not, write to the Free Software

+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

+ */

+

+/**

+ * @file

+ * Libavfilter multithreading support

+ */

+

+#include "config.h"

+

+#include "libavutil/common.h"

+#include "libavutil/cpu.h"

+#include "libavutil/mem.h"

+

+#include "avfilter.h"

+#include "internal.h"

+#include "thread.h"

+

+#if HAVE_PTHREADS

+#include <pthread.h>

+#elif HAVE_W32THREADS

+#include "compat/w32pthreads.h"

+#endif

+

+typedef struct ThreadContext {

+    AVFilterGraph *graph;

+

+    int nb_threads;

+    pthread_t *workers;

+    action_func *func;

+

+    /* per-execute perameters */

+    AVFilterContext *ctx;

+    void *arg;

+    int   *rets;

+    int nb_rets;

+    int nb_jobs;

+

+    pthread_cond_t last_job_cond;

+    pthread_cond_t current_job_cond;

+    pthread_mutex_t current_job_lock;

+    int current_job;

+    int done;

+} ThreadContext;

+

+static void* attribute_align_arg worker(void *v)

+{

+    ThreadContext *c = v;

+    int our_job      = c->nb_jobs;

+    int nb_threads   = c->nb_threads;

+    int self_id;

+

+    pthread_mutex_lock(&c->current_job_lock);

+    self_id = c->current_job++;

+    for (;;) {

+        while (our_job >= c->nb_jobs) {

+            if (c->current_job == nb_threads + c->nb_jobs)

+                pthread_cond_signal(&c->last_job_cond);

+

+            pthread_cond_wait(&c->current_job_cond, &c->current_job_lock);

+            our_job = self_id;

+

+            if (c->done) {

+                pthread_mutex_unlock(&c->current_job_lock);

+                return NULL;

+            }

+        }

+        pthread_mutex_unlock(&c->current_job_lock);

+

+        c->rets[our_job % c->nb_rets] = c->func(c->ctx, c->arg, our_job, c->nb_jobs);

+

+        pthread_mutex_lock(&c->current_job_lock);

+        our_job = c->current_job++;

+    }

+}

+

+static void slice_thread_uninit(ThreadContext *c)

+{

+    int i;

+

+    pthread_mutex_lock(&c->current_job_lock);

+    c->done = 1;

+    pthread_cond_broadcast(&c->current_job_cond);

+    pthread_mutex_unlock(&c->current_job_lock);

+

+    for (i = 0; i < c->nb_threads; i++)

+         pthread_join(c->workers[i], NULL);

+

+    pthread_mutex_destroy(&c->current_job_lock);

+    pthread_cond_destroy(&c->current_job_cond);

+    pthread_cond_destroy(&c->last_job_cond);

+    av_freep(&c->workers);

+}

+

+static void slice_thread_park_workers(ThreadContext *c)

+{

+    pthread_cond_wait(&c->last_job_cond, &c->current_job_lock);

+    pthread_mutex_unlock(&c->current_job_lock);

+}

+

+static int thread_execute(AVFilterContext *ctx, action_func *func,

+                          void *arg, int *ret, int nb_jobs)

+{

+    ThreadContext *c = ctx->graph->internal->thread;

+    int dummy_ret;

+

+    if (nb_jobs <= 0)

+        return 0;

+

+    pthread_mutex_lock(&c->current_job_lock);

+

+    c->current_job = c->nb_threads;

+    c->nb_jobs     = nb_jobs;

+    c->ctx         = ctx;

+    c->arg         = arg;

+    c->func        = func;

+    if (ret) {

+        c->rets    = ret;

+        c->nb_rets = nb_jobs;

+    } else {

+        c->rets    = &dummy_ret;

+        c->nb_rets = 1;

+    }

+    pthread_cond_broadcast(&c->current_job_cond);

+

+    slice_thread_park_workers(c);

+

+    return 0;

+}

+

+static int thread_init(ThreadContext *c, int nb_threads)

+{

+    int i, ret;

+

+    if (!nb_threads) {

+        int nb_cpus = av_cpu_count();

+        av_log(c->graph, AV_LOG_DEBUG, "Detected %d logical cores.\n", nb_cpus);

+        // use number of cores + 1 as thread count if there is more than one

+        if (nb_cpus > 1)

+            nb_threads = nb_cpus + 1;

+        else

+            nb_threads = 1;

+    }

+

+    if (nb_threads <= 1)

+        return 1;

+

+    c->nb_threads = nb_threads;

+    c->workers = av_mallocz(sizeof(*c->workers) * nb_threads);

+    if (!c->workers)

+        return AVERROR(ENOMEM);

+

+    c->current_job = 0;

+    c->nb_jobs     = 0;

+    c->done        = 0;

+

+    pthread_cond_init(&c->current_job_cond, NULL);

+    pthread_cond_init(&c->last_job_cond,    NULL);

+

+    pthread_mutex_init(&c->current_job_lock, NULL);

+    pthread_mutex_lock(&c->current_job_lock);

+    for (i = 0; i < nb_threads; i++) {

+        ret = pthread_create(&c->workers[i], NULL, worker, c);

+        if (ret) {

+           pthread_mutex_unlock(&c->current_job_lock);

+           c->nb_threads = i;

+           slice_thread_uninit(c);

+           return AVERROR(ret);

+        }

+    }

+

+    slice_thread_park_workers(c);

+

+    return c->nb_threads;

+}

+

+int ff_graph_thread_init(AVFilterGraph *graph)

+{

+    int ret;

+

+#if HAVE_W32THREADS

+    w32thread_init();

+#endif

+

+    if (graph->nb_threads == 1) {

+        graph->thread_type = 0;

+        return 0;

+    }

+

+    graph->internal->thread = av_mallocz(sizeof(ThreadContext));

+    if (!graph->internal->thread)

+        return AVERROR(ENOMEM);

+

+    ret = thread_init(graph->internal->thread, graph->nb_threads);

+    if (ret <= 1) {

+        av_freep(&graph->internal->thread);

+        graph->thread_type = 0;

+        graph->nb_threads  = 1;

+        return (ret < 0) ? ret : 0;

+    }

+    graph->nb_threads = ret;

+

+    graph->internal->thread_execute = thread_execute;

+

+    return 0;

+}

+

+void ff_graph_thread_free(AVFilterGraph *graph)

+{

+    if (graph->internal->thread)

+        slice_thread_uninit(graph->internal->thread);

+    av_freep(&graph->internal->thread);

+}

new file mode 100644

@@ -0,0 +1,31 @@

+/*

+ *

+ * This file is part of Libav.

+ *

+ * Libav 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.

+ *

+ * Libav 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 Libav; if not, write to the Free Software

+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

+ */

+

+#ifndef AVFILTER_THREAD_H

+#define AVFILTER_THREAD_H

+

+#include "avfilter.h"

+

+typedef int (action_func)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs);

+

+int ff_graph_thread_init(AVFilterGraph *graph);

+

+void ff_graph_thread_free(AVFilterGraph *graph);

+

+#endif /* AVFILTER_THREAD_H */

@@ -30,7 +30,7 @@

 #include "libavutil/avutil.h"

 #define LIBAVFILTER_VERSION_MAJOR  3

-#define LIBAVFILTER_VERSION_MINOR  9

+#define LIBAVFILTER_VERSION_MINOR  10

 #define LIBAVFILTER_VERSION_MICRO  0

 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \