lavfi: add zmq filters

Changelog

@@ -45,6 +45,7 @@ version <next>:
 - RSD demuxer
 - RedSpark demuxer
 - ADPCM IMA Radical decoder
+- zmq filters
 
 
 version 1.2:

configure

@@ -236,6 +236,7 @@ External library support:
   --enable-libxavs         enable AVS encoding via xavs [no]
   --enable-libxvid         enable Xvid encoding via xvidcore,
                            native MPEG-4/Xvid encoder exists [no]
+  --enable-libzmq          enable message passing via libzmq [no]
   --enable-openal          enable OpenAL 1.1 capture support [no]
   --enable-opencl          enable OpenCL code
   --enable-openssl         enable openssl [no]
@@ -1195,6 +1196,7 @@ EXTERNAL_LIBRARY_LIST="
     libx264
     libxavs
     libxvid
+    libzmq
     openal
     opencl
     openssl
@@ -2122,6 +2124,7 @@ aresample_filter_deps="swresample"
 ass_filter_deps="libass"
 asyncts_filter_deps="avresample"
 atempo_filter_deps="avcodec rdft"
+azmq_filter_deps="libzmq"
 blackframe_filter_deps="gpl"
 boxblur_filter_deps="gpl"
 colormatrix_filter_deps="gpl"
@@ -2166,6 +2169,7 @@ yadif_filter_deps="gpl"
 pixfmts_super2xsai_test_deps="super2xsai_filter"
 tinterlace_merge_test_deps="tinterlace_filter"
 tinterlace_pad_test_deps="tinterlace_filter"
+zmq_filter_deps="libzmq"
 
 # libraries
 avcodec_deps="avutil"
@@ -4055,6 +4059,7 @@ enabled libx264    && require  libx264 x264.h x264_encoder_encode -lx264 &&
                         die "ERROR: libx264 must be installed and version must be >= 0.118."; }
 enabled libxavs    && require  libxavs xavs.h xavs_encoder_encode -lxavs
 enabled libxvid    && require  libxvid xvid.h xvid_global -lxvidcore
+enabled libzmq     && require_pkg_config libzmq zmq.h zmq_ctx_new
 enabled openal     && { { for al_libs in "${OPENAL_LIBS}" "-lopenal" "-lOpenAL32"; do
                         check_lib 'AL/al.h' alGetError "${al_libs}" && break; done } ||
                         die "ERROR: openal not found"; } &&

doc/filters.texi

@@ -8371,6 +8371,48 @@ ffmpeg -i INPUT -filter_complex asplit=5 OUTPUT
 @end example
 @end itemize
 
+@section zmq, azmq
+
+Receive commands sent through a libzmq client, and forward them to
+filters in the filtergraph.
+
+@code{zmq} and @code{azmq} work as a pass-through filters. @code{zmq}
+must be inserted between two video filters, @code{azmq} between two
+audio filters.
+
+To enable these filters you need to install the libzmq library and
+headers and configure FFmpeg with @code{--enable-libzmq}.
+
+For more information about libzmq see:
+@url{http://www.zeromq.org/}
+
+The @code{zmq} and @code{azmq} filters work as a libzmq server, which
+receives messages sent through a network interface defined by the
+@option{bind_address} option.
+
+The received message must be in the form:
+@example
+@var{TARGET} @var{COMMAND} [@var{ARG}]
+@end example
+
+@var{TARGET} specifies the target of the command, usually the name of
+the filter class or a specific filter instance name.
+
+@var{COMMAND} specifies the name of the command for the target filter.
+
+@var{ARG} is optional and specifies the optional argument list for the
+given @var{COMMAND}.
+
+Upon reception, the message is processed and the corresponding command
+is injected into the filtergraph. Depending on the result, the filter
+will send a reply to the client, adopting the format:
+@example
+@var{ERROR_CODE} @var{ERROR_REASON}
+@var{MESSAGE}
+@end example
+
+@var{MESSAGE} is optional.
+
 @c man end MULTIMEDIA FILTERS
 
 @chapter Multimedia Sources

libavfilter/Makefile

@@ -74,6 +74,7 @@ OBJS-$(CONFIG_ASTREAMSYNC_FILTER)            += af_astreamsync.o
 OBJS-$(CONFIG_ASYNCTS_FILTER)                += af_asyncts.o
 OBJS-$(CONFIG_ATEMPO_FILTER)                 += af_atempo.o
 OBJS-$(CONFIG_ATRIM_FILTER)                  += trim.o
+OBJS-$(CONFIG_AZMQ_FILTER)                   += f_zmq.o
 OBJS-$(CONFIG_BANDPASS_FILTER)               += af_biquads.o
 OBJS-$(CONFIG_BANDREJECT_FILTER)             += af_biquads.o
 OBJS-$(CONFIG_BASS_FILTER)                   += af_biquads.o
@@ -187,6 +188,7 @@ OBJS-$(CONFIG_VFLIP_FILTER)                  += vf_vflip.o
 OBJS-$(CONFIG_VIDSTABDETECT_FILTER)          += vidstabutils.o vf_vidstabdetect.o
 OBJS-$(CONFIG_VIDSTABTRANSFORM_FILTER)       += vidstabutils.o vf_vidstabtransform.o
 OBJS-$(CONFIG_YADIF_FILTER)                  += vf_yadif.o
+OBJS-$(CONFIG_ZMQ_FILTER)                    += f_zmq.o
 
 OBJS-$(CONFIG_CELLAUTO_FILTER)               += vsrc_cellauto.o
 OBJS-$(CONFIG_COLOR_FILTER)                  += vsrc_testsrc.o

libavfilter/allfilters.c

@@ -72,6 +72,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(ASYNCTS,        asyncts,        af);
     REGISTER_FILTER(ATEMPO,         atempo,         af);
     REGISTER_FILTER(ATRIM,          atrim,          af);
+    REGISTER_FILTER(AZMQ,           azmq,           af);
     REGISTER_FILTER(BANDPASS,       bandpass,       af);
     REGISTER_FILTER(BANDREJECT,     bandreject,     af);
     REGISTER_FILTER(BASS,           bass,           af);
@@ -184,6 +185,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(VIDSTABDETECT,  vidstabdetect,  vf);
     REGISTER_FILTER(VIDSTABTRANSFORM, vidstabtransform, vf);
     REGISTER_FILTER(YADIF,          yadif,          vf);
+    REGISTER_FILTER(ZMQ,            zmq,            vf);
 
     REGISTER_FILTER(CELLAUTO,       cellauto,       vsrc);
     REGISTER_FILTER(COLOR,          color,          vsrc);

libavfilter/f_zmq.c

@@ -0,0 +1,276 @@
+/*
+ * Copyright (c) 2013 Stefano Sabatini
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * receive commands through libzeromq and broker them to filters
+ */
+
+#include <zmq.h>
+#include "libavutil/avstring.h"
+#include "libavutil/bprint.h"
+#include "libavutil/opt.h"
+#include "avfilter.h"
+#include "internal.h"
+#include "avfiltergraph.h"
+#include "audio.h"
+#include "video.h"
+
+typedef struct {
+    const AVClass *class;
+    void *zmq;
+    void *responder;
+    char *bind_address;
+    int command_count;
+} ZMQContext;
+
+#define OFFSET(x) offsetof(ZMQContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_VIDEO_PARAM
+static const AVOption options[] = {
+    { "bind_address", "set bind address", OFFSET(bind_address), AV_OPT_TYPE_STRING, {.str = "tcp://*:5555"}, 0, 0, FLAGS },
+    { "b",            "set bind address", OFFSET(bind_address), AV_OPT_TYPE_STRING, {.str = "tcp://*:5555"}, 0, 0, FLAGS },
+    { NULL }
+};
+
+static av_cold int init(AVFilterContext *ctx)
+{
+    ZMQContext *zmq = ctx->priv;
+
+    zmq->zmq = zmq_ctx_new();
+    if (!zmq->zmq) {
+        av_log(ctx, AV_LOG_ERROR,
+               "Could not create ZMQ context: %s\n", zmq_strerror(errno));
+        return AVERROR_EXTERNAL;
+    }
+
+    zmq->responder = zmq_socket(zmq->zmq, ZMQ_REP);
+    if (!zmq->responder) {
+        av_log(ctx, AV_LOG_ERROR,
+               "Could not create ZMQ socket: %s\n", zmq_strerror(errno));
+        return AVERROR_EXTERNAL;
+    }
+
+    if (zmq_bind(zmq->responder, zmq->bind_address) == -1) {
+        av_log(ctx, AV_LOG_ERROR,
+               "Could not bind ZMQ socket to address '%s': %s\n",
+               zmq->bind_address, zmq_strerror(errno));
+        return AVERROR_EXTERNAL;
+    }
+
+    zmq->command_count = -1;
+    return 0;
+}
+
+static void av_cold uninit(AVFilterContext *ctx)
+{
+    ZMQContext *zmq = ctx->priv;
+
+    zmq_close(zmq->responder);
+    zmq_ctx_destroy(zmq->zmq);
+}
+
+typedef struct {
+    char *target, *command, *arg;
+} Command;
+
+#define SPACES " \f\t\n\r"
+
+static int parse_command(Command *cmd, const char *command_str, void *log_ctx)
+{
+    const char **buf = &command_str;
+
+    cmd->target = av_get_token(buf, SPACES);
+    if (!cmd->target || !cmd->target[0]) {
+        av_log(log_ctx, AV_LOG_ERROR,
+               "No target specified in command '%s'\n", command_str);
+        return AVERROR(EINVAL);
+    }
+
+    cmd->command = av_get_token(buf, SPACES);
+    if (!cmd->command || !cmd->command[0]) {
+        av_log(log_ctx, AV_LOG_ERROR,
+               "No command specified in command '%s'\n", command_str);
+        return AVERROR(EINVAL);
+    }
+
+    cmd->arg = av_get_token(buf, SPACES);
+    return 0;
+}
+
+static int recv_msg(AVFilterContext *ctx, char **buf, int *buf_size)
+{
+    ZMQContext *zmq = ctx->priv;
+    zmq_msg_t msg;
+    int ret = 0;
+
+    if (zmq_msg_init(&msg) == -1) {
+        av_log(ctx, AV_LOG_WARNING,
+               "Could not initialize receive message: %s\n", zmq_strerror(errno));
+        return AVERROR_EXTERNAL;
+    }
+
+    if (zmq_msg_recv(&msg, zmq->responder, ZMQ_DONTWAIT) == -1) {
+        if (errno != EAGAIN)
+            av_log(ctx, AV_LOG_WARNING,
+                   "Could not receive message: %s\n", zmq_strerror(errno));
+        ret = AVERROR_EXTERNAL;
+        goto end;
+    }
+
+    *buf_size = zmq_msg_size(&msg) + 1;
+    *buf = av_malloc(*buf_size);
+    if (!*buf) {
+        ret = AVERROR(ENOMEM);
+        goto end;
+    }
+    memcpy(*buf, zmq_msg_data(&msg), *buf_size);
+    (*buf)[*buf_size-1] = 0;
+
+end:
+    zmq_msg_close(&msg);
+    return ret;
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *ref)
+{
+    AVFilterContext *ctx = inlink->dst;
+    ZMQContext *zmq = ctx->priv;
+
+    while (1) {
+        char cmd_buf[1024];
+        char *recv_buf, *send_buf;
+        int recv_buf_size;
+        Command cmd = {0};
+        int ret;
+
+        /* receive command */
+        if (recv_msg(ctx, &recv_buf, &recv_buf_size) < 0)
+            break;
+        zmq->command_count++;
+
+        /* parse command */
+        if (parse_command(&cmd, recv_buf, ctx) < 0) {
+            av_log(ctx, AV_LOG_ERROR, "Could not parse command #%d\n", zmq->command_count);
+            goto end;
+        }
+
+        /* process command */
+        av_log(ctx, AV_LOG_VERBOSE,
+               "Processing command #%d target:%s command:%s arg:%s\n",
+               zmq->command_count, cmd.target, cmd.command, cmd.arg);
+        ret = avfilter_graph_send_command(inlink->graph,
+                                          cmd.target, cmd.command, cmd.arg,
+                                          cmd_buf, sizeof(cmd_buf),
+                                          AVFILTER_CMD_FLAG_ONE);
+        send_buf = av_asprintf("%d %s%s%s",
+                               -ret, av_err2str(ret), cmd_buf[0] ? "\n" : "", cmd_buf);
+        if (!send_buf) {
+            ret = AVERROR(ENOMEM);
+            goto end;
+        }
+        av_log(ctx, AV_LOG_VERBOSE,
+               "Sending command reply for command #%d:\n%s\n",
+               zmq->command_count, send_buf);
+        if (zmq_send(zmq->responder, send_buf, strlen(send_buf), 0) == -1)
+            av_log(ctx, AV_LOG_ERROR, "Failed to send reply for command #%d: %s\n",
+                   zmq->command_count, zmq_strerror(ret));
+
+    end:
+        av_freep(&send_buf);
+        av_freep(&recv_buf);
+        recv_buf_size = 0;
+        av_freep(&cmd.target);
+        av_freep(&cmd.command);
+        av_freep(&cmd.arg);
+    }
+
+    return ff_filter_frame(ctx->outputs[0], ref);
+}
+
+#if CONFIG_ZMQ_FILTER
+
+#define zmq_options options
+AVFILTER_DEFINE_CLASS(zmq);
+
+static const AVFilterPad zmq_inputs[] = {
+    {
+        .name             = "default",
+        .type             = AVMEDIA_TYPE_VIDEO,
+        .filter_frame     = filter_frame,
+    },
+    { NULL }
+};
+
+static const AVFilterPad zmq_outputs[] = {
+    {
+        .name = "default",
+        .type = AVMEDIA_TYPE_VIDEO,
+    },
+    { NULL }
+};
+
+AVFilter avfilter_vf_zmq = {
+    .name        = "zmq",
+    .description = NULL_IF_CONFIG_SMALL("Receive commands through ZMQ and broker them to filters."),
+    .init        = init,
+    .uninit      = uninit,
+    .priv_size   = sizeof(ZMQContext),
+    .inputs      = zmq_inputs,
+    .outputs     = zmq_outputs,
+    .priv_class  = &zmq_class,
+};
+
+#endif
+
+#if CONFIG_AZMQ_FILTER
+
+#define azmq_options options
+AVFILTER_DEFINE_CLASS(azmq);
+
+static const AVFilterPad azmq_inputs[] = {
+    {
+        .name             = "default",
+        .type             = AVMEDIA_TYPE_AUDIO,
+        .get_audio_buffer = ff_null_get_audio_buffer,
+        .filter_frame     = filter_frame,
+    },
+    { NULL }
+};
+
+static const AVFilterPad azmq_outputs[] = {
+    {
+        .name = "default",
+        .type = AVMEDIA_TYPE_AUDIO,
+    },
+    { NULL }
+};
+
+AVFilter avfilter_af_azmq = {
+    .name        = "azmq",
+    .description = NULL_IF_CONFIG_SMALL("Receive commands through ZMQ and broker them to filters."),
+    .init        = init,
+    .uninit      = uninit,
+    .priv_size   = sizeof(ZMQContext),
+    .inputs      = azmq_inputs,
+    .outputs     = azmq_outputs,
+    .priv_class  = &azmq_class,
+};
+
+#endif

libavfilter/version.h

@@ -29,7 +29,7 @@
 #include "libavutil/avutil.h"
 
 #define LIBAVFILTER_VERSION_MAJOR  3
-#define LIBAVFILTER_VERSION_MINOR  65
+#define LIBAVFILTER_VERSION_MINOR  66
 #define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \