FFmpeg
vf_fieldorder.c
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1 /*
2  * Copyright (c) 2011 Mark Himsley
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * video field order filter, heavily influenced by vf_pad.c
24  */
25 
26 #include "libavutil/imgutils.h"
27 #include "libavutil/internal.h"
28 #include "libavutil/opt.h"
29 #include "libavutil/pixdesc.h"
30 #include "avfilter.h"
31 #include "formats.h"
32 #include "internal.h"
33 #include "video.h"
34 
35 typedef struct FieldOrderContext {
36  const AVClass *class;
37  int dst_tff; ///< output bff/tff
38  int line_size[4]; ///< bytes of pixel data per line for each plane
40 
42 {
45  int ret;
46 
47  /** accept any input pixel format that is not hardware accelerated, not
48  * a bitstream format, and does not have vertically sub-sampled chroma */
49  if (ctx->inputs[0]) {
50  const AVPixFmtDescriptor *desc = NULL;
51  formats = NULL;
52  while ((desc = av_pix_fmt_desc_next(desc))) {
53  pix_fmt = av_pix_fmt_desc_get_id(desc);
54  if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL ||
55  desc->flags & AV_PIX_FMT_FLAG_PAL ||
57  desc->nb_components && !desc->log2_chroma_h &&
58  (ret = ff_add_format(&formats, pix_fmt)) < 0)
59  return ret;
60  }
61  if ((ret = ff_formats_ref(formats, &ctx->inputs[0]->out_formats)) < 0 ||
62  (ret = ff_formats_ref(formats, &ctx->outputs[0]->in_formats)) < 0)
63  return ret;
64  }
65 
66  return 0;
67 }
68 
70 {
71  AVFilterContext *ctx = inlink->dst;
72  FieldOrderContext *s = ctx->priv;
73 
74  return av_image_fill_linesizes(s->line_size, inlink->format, inlink->w);
75 }
76 
78 {
79  AVFilterContext *ctx = inlink->dst;
80  FieldOrderContext *s = ctx->priv;
81  AVFilterLink *outlink = ctx->outputs[0];
82  int h, plane, src_line_step, dst_line_step, line_size, line;
83  uint8_t *dst, *src;
84  AVFrame *out;
85 
86  if (!frame->interlaced_frame ||
87  frame->top_field_first == s->dst_tff) {
89  "Skipping %s.\n",
90  frame->interlaced_frame ?
91  "frame with same field order" : "progressive frame");
92  return ff_filter_frame(outlink, frame);
93  }
94 
95  if (av_frame_is_writable(frame)) {
96  out = frame;
97  } else {
98  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
99  if (!out) {
100  av_frame_free(&frame);
101  return AVERROR(ENOMEM);
102  }
103  av_frame_copy_props(out, frame);
104  }
105 
106  av_log(ctx, AV_LOG_TRACE,
107  "picture will move %s one line\n",
108  s->dst_tff ? "up" : "down");
109  h = frame->height;
110  for (plane = 0; plane < 4 && frame->data[plane] && frame->linesize[plane]; plane++) {
111  dst_line_step = out->linesize[plane] * (h > 2);
112  src_line_step = frame->linesize[plane] * (h > 2);
113  line_size = s->line_size[plane];
114  dst = out->data[plane];
115  src = frame->data[plane];
116  if (s->dst_tff) {
117  /** Move every line up one line, working from
118  * the top to the bottom of the frame.
119  * The original top line is lost.
120  * The new last line is created as a copy of the
121  * penultimate line from that field. */
122  for (line = 0; line < h; line++) {
123  if (1 + line < frame->height) {
124  memcpy(dst, src + src_line_step, line_size);
125  } else {
126  memcpy(dst, src - 2 * src_line_step, line_size);
127  }
128  dst += dst_line_step;
129  src += src_line_step;
130  }
131  } else {
132  /** Move every line down one line, working from
133  * the bottom to the top of the frame.
134  * The original bottom line is lost.
135  * The new first line is created as a copy of the
136  * second line from that field. */
137  dst += (h - 1) * dst_line_step;
138  src += (h - 1) * src_line_step;
139  for (line = h - 1; line >= 0 ; line--) {
140  if (line > 0) {
141  memcpy(dst, src - src_line_step, line_size);
142  } else {
143  memcpy(dst, src + 2 * src_line_step, line_size);
144  }
145  dst -= dst_line_step;
146  src -= src_line_step;
147  }
148  }
149  }
150  out->top_field_first = s->dst_tff;
151 
152  if (frame != out)
153  av_frame_free(&frame);
154  return ff_filter_frame(outlink, out);
155 }
156 
157 #define OFFSET(x) offsetof(FieldOrderContext, x)
158 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
159 
160 static const AVOption fieldorder_options[] = {
161  { "order", "output field order", OFFSET(dst_tff), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, FLAGS, "order" },
162  { "bff", "bottom field first", 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, .flags=FLAGS, .unit = "order" },
163  { "tff", "top field first", 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, .flags=FLAGS, .unit = "order" },
164  { NULL }
165 };
166 
167 AVFILTER_DEFINE_CLASS(fieldorder);
168 
170  {
171  .name = "default",
172  .type = AVMEDIA_TYPE_VIDEO,
173  .config_props = config_input,
174  .filter_frame = filter_frame,
175  },
176  { NULL }
177 };
178 
180  {
181  .name = "default",
182  .type = AVMEDIA_TYPE_VIDEO,
183  },
184  { NULL }
185 };
186 
188  .name = "fieldorder",
189  .description = NULL_IF_CONFIG_SMALL("Set the field order."),
190  .priv_size = sizeof(FieldOrderContext),
191  .priv_class = &fieldorder_class,
193  .inputs = avfilter_vf_fieldorder_inputs,
194  .outputs = avfilter_vf_fieldorder_outputs,
196 };
#define AV_PIX_FMT_FLAG_PAL
Pixel format has a palette in data[1], values are indexes in this palette.
Definition: pixdesc.h:132
int plane
Definition: avisynth_c.h:384
AVFilter ff_vf_fieldorder
#define NULL
Definition: coverity.c:32
static enum AVPixelFormat pix_fmt
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
static const AVOption fieldorder_options[]
AVOption.
Definition: opt.h:246
misc image utilities
Main libavfilter public API header.
const char * desc
Definition: nvenc.c:68
static int query_formats(AVFilterContext *ctx)
Definition: vf_fieldorder.c:41
AVFrame * ff_get_video_buffer(AVFilterLink *link, int w, int h)
Request a picture buffer with a specific set of permissions.
Definition: video.c:99
#define src
Definition: vp8dsp.c:254
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:125
const char * name
Pad name.
Definition: internal.h:60
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:346
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1093
uint8_t
AVOptions.
#define AV_LOG_TRACE
Extremely verbose debugging, useful for libav* development.
Definition: log.h:202
int dst_tff
output bff/tff
Definition: vf_fieldorder.c:37
AVFILTER_DEFINE_CLASS(fieldorder)
#define height
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
int interlaced_frame
The content of the picture is interlaced.
Definition: frame.h:442
static const AVFilterPad avfilter_vf_fieldorder_inputs[]
#define av_log(a,...)
A filter pad used for either input or output.
Definition: internal.h:54
int line_size[4]
bytes of pixel data per line for each plane
Definition: vf_fieldorder.c:38
uint8_t log2_chroma_h
Amount to shift the luma height right to find the chroma height.
Definition: pixdesc.h:101
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void * priv
private data for use by the filter
Definition: avfilter.h:353
Definition: graph2dot.c:48
#define AV_PIX_FMT_FLAG_HWACCEL
Pixel format is an HW accelerated format.
Definition: pixdesc.h:140
int ff_add_format(AVFilterFormats **avff, int64_t fmt)
Add fmt to the list of media formats contained in *avff.
Definition: formats.c:336
#define FLAGS
common internal API header
uint64_t flags
Combination of AV_PIX_FMT_FLAG_...
Definition: pixdesc.h:106
enum AVPixelFormat av_pix_fmt_desc_get_id(const AVPixFmtDescriptor *desc)
Definition: pixdesc.c:2541
uint8_t nb_components
The number of components each pixel has, (1-4)
Definition: pixdesc.h:83
int ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
Add *ref as a new reference to formats.
Definition: formats.c:439
AVFormatContext * ctx
Definition: movenc.c:48
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define s(width, name)
Definition: cbs_vp9.c:257
#define OFFSET(x)
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:594
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
int av_image_fill_linesizes(int linesizes[4], enum AVPixelFormat pix_fmt, int width)
Fill plane linesizes for an image with pixel format pix_fmt and width width.
Definition: imgutils.c:89
const char * name
Filter name.
Definition: avfilter.h:148
#define AV_PIX_FMT_FLAG_BITSTREAM
All values of a component are bit-wise packed end to end.
Definition: pixdesc.h:136
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
static const AVFilterPad avfilter_vf_fieldorder_outputs[]
static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
Definition: vf_fieldorder.c:77
#define flags(name, subs,...)
Definition: cbs_av1.c:561
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
The official guide to swscale for confused that consecutive non overlapping rectangles of slice_bottom special converter These generally are unscaled converters of common like for each output line the vertical scaler pulls lines from a ring buffer When the ring buffer does not contain the wanted line
Definition: swscale.txt:33
static int config_input(AVFilterLink *inlink)
Definition: vf_fieldorder.c:69
int top_field_first
If the content is interlaced, is top field displayed first.
Definition: frame.h:447
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:338
int height
Definition: frame.h:353
FILE * out
Definition: movenc.c:54
formats
Definition: signature.h:48
internal API functions
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:654
const AVPixFmtDescriptor * av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)
Iterate over all pixel format descriptors known to libavutil.
Definition: pixdesc.c:2529