Commit 1bf7bd19 authored by Paul B Mahol's avatar Paul B Mahol

avfilter: add ocr filter

Signed-off-by: 's avatarPaul B Mahol <onemda@gmail.com>
parent 494b7924
......@@ -4,6 +4,7 @@ releases are sorted from youngest to oldest.
version <next>:
- DXV decoding
- extrastereo filter
- ocr filter
version 2.8:
......
......@@ -246,6 +246,7 @@ External library support:
--enable-libspeex enable Speex de/encoding via libspeex [no]
--enable-libssh enable SFTP protocol via libssh [no]
--enable-libstagefright-h264 enable H.264 decoding via libstagefright [no]
--enable-libtesseract enable Tesseract, needed for ocr filter [no]
--enable-libtheora enable Theora encoding via libtheora [no]
--enable-libtwolame enable MP2 encoding via libtwolame [no]
--enable-libutvideo enable Ut Video encoding and decoding via libutvideo [no]
......@@ -1409,6 +1410,7 @@ EXTERNAL_LIBRARY_LIST="
libspeex
libssh
libstagefright_h264
libtesseract
libtheora
libtwolame
libutvideo
......@@ -2774,6 +2776,7 @@ mptestsrc_filter_deps="gpl"
negate_filter_deps="lut_filter"
perspective_filter_deps="gpl"
pp7_filter_deps="gpl"
ocr_filter_deps="libtesseract"
ocv_filter_deps="libopencv"
owdenoise_filter_deps="gpl"
pan_filter_deps="swresample"
......@@ -5275,6 +5278,7 @@ enabled libspeex && require_pkg_config speex speex/speex.h speex_decode
enabled libstagefright_h264 && require_cpp libstagefright_h264 "binder/ProcessState.h media/stagefright/MetaData.h
media/stagefright/MediaBufferGroup.h media/stagefright/MediaDebug.h media/stagefright/MediaDefs.h
media/stagefright/OMXClient.h media/stagefright/OMXCodec.h" android::OMXClient -lstagefright -lmedia -lutils -lbinder -lgnustl_static
enabled libtesseract && require_pkg_config tesseract tesseract/capi.h TessBaseAPICreate
enabled libtheora && require libtheora theora/theoraenc.h th_info_init -ltheoraenc -ltheoradec -logg
enabled libtwolame && require libtwolame twolame.h twolame_init -ltwolame &&
{ check_lib twolame.h twolame_encode_buffer_float32_interleaved -ltwolame ||
......
......@@ -7485,6 +7485,30 @@ noise=alls=20:allf=t+u
Pass the video source unchanged to the output.
@section ocr
Optical Character Recognition
This filter uses Tesseract for optical character recognition.
It accepts the following options:
@table @option
@item datapath
Set datapath to tesseract data. Default is to use whatever was
set at installation.
@item language
Set language, default is "eng".
@item whitelist
Set character whitelist.
@item blacklist
Set character blacklist.
@end table
The filter exports recognized text as the frame metadata @code{lavfi.ocr.text}.
@section ocv
Apply a video transform using libopencv.
......
......@@ -169,6 +169,7 @@ OBJS-$(CONFIG_NEGATE_FILTER) += vf_lut.o
OBJS-$(CONFIG_NOFORMAT_FILTER) += vf_format.o
OBJS-$(CONFIG_NOISE_FILTER) += vf_noise.o
OBJS-$(CONFIG_NULL_FILTER) += vf_null.o
OBJS-$(CONFIG_OCR_FILTER) += vf_ocr.o
OBJS-$(CONFIG_OCV_FILTER) += vf_libopencv.o
OBJS-$(CONFIG_OPENCL) += deshake_opencl.o unsharp_opencl.o
OBJS-$(CONFIG_OVERLAY_FILTER) += vf_overlay.o dualinput.o framesync.o
......
......@@ -191,6 +191,7 @@ void avfilter_register_all(void)
REGISTER_FILTER(NOFORMAT, noformat, vf);
REGISTER_FILTER(NOISE, noise, vf);
REGISTER_FILTER(NULL, null, vf);
REGISTER_FILTER(OCR, ocr, vf);
REGISTER_FILTER(OCV, ocv, vf);
REGISTER_FILTER(OVERLAY, overlay, vf);
REGISTER_FILTER(OWDENOISE, owdenoise, vf);
......
......@@ -30,7 +30,7 @@
#include "libavutil/version.h"
#define LIBAVFILTER_VERSION_MAJOR 6
#define LIBAVFILTER_VERSION_MINOR 1
#define LIBAVFILTER_VERSION_MINOR 2
#define LIBAVFILTER_VERSION_MICRO 100
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
......
/*
* Copyright (c) 2015 Paul B Mahol
*
* 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 <tesseract/capi.h>
#include "libavutil/opt.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
typedef struct OCRContext {
const AVClass *class;
char *datapath;
char *language;
char *whitelist;
char *blacklist;
TessBaseAPI *tess;
} OCRContext;
#define OFFSET(x) offsetof(OCRContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption ocr_options[] = {
{ "datapath", "set datapath", OFFSET(datapath), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
{ "language", "set language", OFFSET(language), AV_OPT_TYPE_STRING, {.str="eng"}, 0, 0, FLAGS },
{ "whitelist", "set character whitelist", OFFSET(whitelist), AV_OPT_TYPE_STRING, {.str="0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ.:;,-+_!?\"'[]{}()<>|/\\=*&%$#@!~"}, 0, 0, FLAGS },
{ "blacklist", "set character blacklist", OFFSET(blacklist), AV_OPT_TYPE_STRING, {.str=""}, 0, 0, FLAGS },
{ NULL }
};
static av_cold int init(AVFilterContext *ctx)
{
OCRContext *s = ctx->priv;
s->tess = TessBaseAPICreate();
if (TessBaseAPIInit3(s->tess, s->datapath, s->language) == -1) {
av_log(ctx, AV_LOG_ERROR, "failed to init tesseract\n");
return AVERROR(EINVAL);
}
if (!TessBaseAPISetVariable(s->tess, "tessedit_char_whitelist", s->whitelist)) {
av_log(ctx, AV_LOG_ERROR, "failed to set whitelist\n");
return AVERROR(EINVAL);
}
if (!TessBaseAPISetVariable(s->tess, "tessedit_char_blacklist", s->blacklist)) {
av_log(ctx, AV_LOG_ERROR, "failed to set blacklist\n");
return AVERROR(EINVAL);
}
av_log(ctx, AV_LOG_DEBUG, "Tesseract version: %s\n", TessVersion());
return 0;
}
static int query_formats(AVFilterContext *ctx)
{
static const enum AVPixelFormat pix_fmts[] = {
AV_PIX_FMT_GRAY8,
AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P,
AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_YUVJ444P,
AV_PIX_FMT_YUVJ411P,
AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA420P,
AV_PIX_FMT_NONE
};
AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
if (!fmts_list)
return AVERROR(ENOMEM);
ff_set_common_formats(ctx, fmts_list);
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
AVDictionary **metadata = avpriv_frame_get_metadatap(in);
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
OCRContext *s = ctx->priv;
char *result;
result = TessBaseAPIRect(s->tess, in->data[0], 1,
in->linesize[0], 0, 0, in->width, in->height);
av_dict_set(metadata, "lavfi.ocr.text", result, 0);
TessDeleteText(result);
return ff_filter_frame(outlink, in);
}
static av_cold void uninit(AVFilterContext *ctx)
{
OCRContext *s = ctx->priv;
TessBaseAPIEnd(s->tess);
TessBaseAPIDelete(s->tess);
}
AVFILTER_DEFINE_CLASS(ocr);
static const AVFilterPad ocr_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad ocr_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter ff_vf_ocr = {
.name = "ocr",
.description = NULL_IF_CONFIG_SMALL("Optical Character Recognition."),
.priv_size = sizeof(OCRContext),
.priv_class = &ocr_class,
.query_formats = query_formats,
.init = init,
.uninit = uninit,
.inputs = ocr_inputs,
.outputs = ocr_outputs,
};
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment