Libav
vf_scale.c
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1 /*
2  * Copyright (c) 2007 Bobby Bingham
3  *
4  * This file is part of Libav.
5  *
6  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
26 #include <stdio.h>
27 #include <string.h>
28 
29 #include "avfilter.h"
30 #include "formats.h"
31 #include "internal.h"
32 #include "video.h"
33 #include "libavutil/avstring.h"
34 #include "libavutil/eval.h"
35 #include "libavutil/internal.h"
36 #include "libavutil/mathematics.h"
37 #include "libavutil/opt.h"
38 #include "libavutil/pixdesc.h"
39 #include "libswscale/swscale.h"
40 
41 static const char *const var_names[] = {
42  "PI",
43  "PHI",
44  "E",
45  "in_w", "iw",
46  "in_h", "ih",
47  "out_w", "ow",
48  "out_h", "oh",
49  "a", "dar",
50  "sar",
51  "hsub",
52  "vsub",
53  NULL
54 };
55 
56 enum var_name {
69 };
70 
71 typedef struct ScaleContext {
72  const AVClass *class;
73  struct SwsContext *sws;
74 
80  int w, h;
81  unsigned int flags;
82  double param[2]; // sws params
83 
84  int hsub, vsub;
85  int slice_y;
87 
88  char *w_expr;
89  char *h_expr;
90  char *flags_str;
91 } ScaleContext;
92 
94 {
95  ScaleContext *scale = ctx->priv;
96 
97  if (scale->flags_str) {
98  const AVClass *class = sws_get_class();
99  const AVOption *o = av_opt_find(&class, "sws_flags", NULL, 0,
101  int ret = av_opt_eval_flags(&class, o, scale->flags_str, &scale->flags);
102 
103  if (ret < 0)
104  return ret;
105  }
106 
107  return 0;
108 }
109 
111 {
112  ScaleContext *scale = ctx->priv;
113  sws_freeContext(scale->sws);
114  scale->sws = NULL;
115 }
116 
118 {
120  enum AVPixelFormat pix_fmt;
121  int ret;
122 
123  if (ctx->inputs[0]) {
124  const AVPixFmtDescriptor *desc = NULL;
125  formats = NULL;
126  while ((desc = av_pix_fmt_desc_next(desc))) {
127  pix_fmt = av_pix_fmt_desc_get_id(desc);
128  if ((sws_isSupportedInput(pix_fmt) ||
130  && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
131  ff_formats_unref(&formats);
132  return ret;
133  }
134  }
135  ff_formats_ref(formats, &ctx->inputs[0]->out_formats);
136  }
137  if (ctx->outputs[0]) {
138  const AVPixFmtDescriptor *desc = NULL;
139  formats = NULL;
140  while ((desc = av_pix_fmt_desc_next(desc))) {
141  pix_fmt = av_pix_fmt_desc_get_id(desc);
142  if ((sws_isSupportedOutput(pix_fmt) ||
144  && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
145  ff_formats_unref(&formats);
146  return ret;
147  }
148  }
149  ff_formats_ref(formats, &ctx->outputs[0]->in_formats);
150  }
151 
152  return 0;
153 }
154 
155 static int config_props(AVFilterLink *outlink)
156 {
157  AVFilterContext *ctx = outlink->src;
158  AVFilterLink *inlink = outlink->src->inputs[0];
159  ScaleContext *scale = ctx->priv;
161  int64_t w, h;
162  double var_values[VARS_NB], res;
163  char *expr;
164  int ret;
165 
166  var_values[VAR_PI] = M_PI;
167  var_values[VAR_PHI] = M_PHI;
168  var_values[VAR_E] = M_E;
169  var_values[VAR_IN_W] = var_values[VAR_IW] = inlink->w;
170  var_values[VAR_IN_H] = var_values[VAR_IH] = inlink->h;
171  var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
172  var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
173  var_values[VAR_A] = (double) inlink->w / inlink->h;
174  var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ?
175  (double) inlink->sample_aspect_ratio.num / inlink->sample_aspect_ratio.den : 1;
176  var_values[VAR_DAR] = var_values[VAR_A] * var_values[VAR_SAR];
177  var_values[VAR_HSUB] = 1 << desc->log2_chroma_w;
178  var_values[VAR_VSUB] = 1 << desc->log2_chroma_h;
179 
180  /* evaluate width and height */
181  av_expr_parse_and_eval(&res, (expr = scale->w_expr),
182  var_names, var_values,
183  NULL, NULL, NULL, NULL, NULL, 0, ctx);
184  scale->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
185  if ((ret = av_expr_parse_and_eval(&res, (expr = scale->h_expr),
186  var_names, var_values,
187  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
188  goto fail;
189  scale->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
190  /* evaluate again the width, as it may depend on the output height */
191  if ((ret = av_expr_parse_and_eval(&res, (expr = scale->w_expr),
192  var_names, var_values,
193  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
194  goto fail;
195  scale->w = res;
196 
197  w = scale->w;
198  h = scale->h;
199 
200  /* sanity check params */
201  if (w < -1 || h < -1) {
202  av_log(ctx, AV_LOG_ERROR, "Size values less than -1 are not acceptable.\n");
203  return AVERROR(EINVAL);
204  }
205  if (w == -1 && h == -1)
206  scale->w = scale->h = 0;
207 
208  if (!(w = scale->w))
209  w = inlink->w;
210  if (!(h = scale->h))
211  h = inlink->h;
212  if (w == -1)
213  w = av_rescale(h, inlink->w, inlink->h);
214  if (h == -1)
215  h = av_rescale(w, inlink->h, inlink->w);
216 
217  if (w > INT_MAX || h > INT_MAX ||
218  (h * inlink->w) > INT_MAX ||
219  (w * inlink->h) > INT_MAX)
220  av_log(ctx, AV_LOG_ERROR, "Rescaled value for width or height is too big.\n");
221 
222  outlink->w = w;
223  outlink->h = h;
224 
225  /* TODO: make algorithm configurable */
226  av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d fmt:%s -> w:%d h:%d fmt:%s flags:0x%0x\n",
227  inlink ->w, inlink ->h, av_get_pix_fmt_name(inlink->format),
228  outlink->w, outlink->h, av_get_pix_fmt_name(outlink->format),
229  scale->flags);
230 
231  scale->input_is_pal = desc->flags & AV_PIX_FMT_FLAG_PAL ||
233 
234  if (scale->sws)
235  sws_freeContext(scale->sws);
236  if (inlink->w == outlink->w && inlink->h == outlink->h &&
237  inlink->format == outlink->format)
238  scale->sws = NULL;
239  else {
240  scale->sws = sws_getContext(inlink ->w, inlink ->h, inlink ->format,
241  outlink->w, outlink->h, outlink->format,
242  scale->flags, NULL, NULL, scale->param);
243  if (!scale->sws)
244  return AVERROR(EINVAL);
245  }
246 
247 
248  if (inlink->sample_aspect_ratio.num)
249  outlink->sample_aspect_ratio = av_mul_q((AVRational){outlink->h*inlink->w,
250  outlink->w*inlink->h},
251  inlink->sample_aspect_ratio);
252  else
253  outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
254 
255  return 0;
256 
257 fail:
259  "Error when evaluating the expression '%s'\n", expr);
260  return ret;
261 }
262 
263 static int filter_frame(AVFilterLink *link, AVFrame *in)
264 {
265  ScaleContext *scale = link->dst->priv;
266  AVFilterLink *outlink = link->dst->outputs[0];
267  AVFrame *out;
269 
270  if (!scale->sws)
271  return ff_filter_frame(outlink, in);
272 
273  scale->hsub = desc->log2_chroma_w;
274  scale->vsub = desc->log2_chroma_h;
275 
276  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
277  if (!out) {
278  av_frame_free(&in);
279  return AVERROR(ENOMEM);
280  }
281 
282  av_frame_copy_props(out, in);
283  out->width = outlink->w;
284  out->height = outlink->h;
285 
287  (int64_t)in->sample_aspect_ratio.num * outlink->h * link->w,
288  (int64_t)in->sample_aspect_ratio.den * outlink->w * link->h,
289  INT_MAX);
290 
291  sws_scale(scale->sws, in->data, in->linesize, 0, in->height,
292  out->data, out->linesize);
293 
294  av_frame_free(&in);
295  return ff_filter_frame(outlink, out);
296 }
297 
298 #define OFFSET(x) offsetof(ScaleContext, x)
299 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM
300 static const AVOption options[] = {
301  { "w", "Output video width", OFFSET(w_expr), AV_OPT_TYPE_STRING, { .str = "iw" }, .flags = FLAGS },
302  { "h", "Output video height", OFFSET(h_expr), AV_OPT_TYPE_STRING, { .str = "ih" }, .flags = FLAGS },
303  { "flags", "Flags to pass to libswscale", OFFSET(flags_str), AV_OPT_TYPE_STRING, { .str = "bilinear" }, .flags = FLAGS },
304  { "param0", "Scaler param 0", OFFSET(param[0]), AV_OPT_TYPE_DOUBLE, { .dbl = SWS_PARAM_DEFAULT }, INT_MIN, INT_MAX, FLAGS },
305  { "param1", "Scaler param 1", OFFSET(param[1]), AV_OPT_TYPE_DOUBLE, { .dbl = SWS_PARAM_DEFAULT }, INT_MIN, INT_MAX, FLAGS },
306  { NULL },
307 };
308 
309 static const AVClass scale_class = {
310  .class_name = "scale",
311  .item_name = av_default_item_name,
312  .option = options,
313  .version = LIBAVUTIL_VERSION_INT,
314 };
315 
317  {
318  .name = "default",
319  .type = AVMEDIA_TYPE_VIDEO,
320  .filter_frame = filter_frame,
321  },
322  { NULL }
323 };
324 
326  {
327  .name = "default",
328  .type = AVMEDIA_TYPE_VIDEO,
329  .config_props = config_props,
330  },
331  { NULL }
332 };
333 
335  .name = "scale",
336  .description = NULL_IF_CONFIG_SMALL("Scale the input video to width:height size and/or convert the image format."),
337 
338  .init = init,
339  .uninit = uninit,
340 
341  .query_formats = query_formats,
342 
343  .priv_size = sizeof(ScaleContext),
344  .priv_class = &scale_class,
345 
346  .inputs = avfilter_vf_scale_inputs,
347  .outputs = avfilter_vf_scale_outputs,
348 };
#define AV_PIX_FMT_FLAG_PAL
Pixel format has a palette in data[1], values are indexes in this palette.
Definition: pixdesc.h:134
int sws_isSupportedOutput(enum AVPixelFormat pix_fmt)
Return a positive value if pix_fmt is a supported output format, 0 otherwise.
Definition: utils.c:198
#define FLAGS
Definition: vf_scale.c:299
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:1768
This structure describes decoded (raw) audio or video data.
Definition: frame.h:140
AVOption.
Definition: opt.h:234
static const AVFilterPad outputs[]
Definition: af_ashowinfo.c:259
Main libavfilter public API header.
const char * desc
Definition: nvenc.c:101
Definition: vf_scale.c:59
int num
numerator
Definition: rational.h:44
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
static enum AVSampleFormat formats[]
Definition: avresample.c:163
int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt)
Definition: utils.c:204
AVFrame * ff_get_video_buffer(AVFilterLink *link, int w, int h)
Request a picture buffer with a specific set of permissions.
Definition: video.c:57
static const AVOption options[]
Definition: vf_scale.c:300
const AVClass * sws_get_class(void)
Get the AVClass for swsContext.
Definition: options.c:71
int vsub
chroma subsampling
Definition: vf_scale.c:84
uint8_t log2_chroma_w
Amount to shift the luma width right to find the chroma width.
Definition: pixdesc.h:91
const char * name
Pad name.
Definition: internal.h:41
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:39
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:270
char * w_expr
width expression string
Definition: vf_scale.c:88
static int query_formats(AVFilterContext *ctx)
Definition: vf_scale.c:117
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:747
#define av_cold
Definition: attributes.h:66
char * h_expr
height expression string
Definition: vf_scale.c:89
AVOptions.
AVRational av_mul_q(AVRational b, AVRational c)
Multiply two rationals.
Definition: rational.c:79
struct SwsContext * sws_getContext(int srcW, int srcH, enum AVPixelFormat srcFormat, int dstW, int dstH, enum AVPixelFormat dstFormat, int flags, SwsFilter *srcFilter, SwsFilter *dstFilter, const double *param)
Allocate and return an SwsContext.
Definition: utils.c:1319
static const AVClass scale_class
Definition: vf_scale.c:309
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:140
external api for the swscale stuff
A filter pad used for either input or output.
Definition: internal.h:35
int av_expr_parse_and_eval(double *d, const char *s, const char *const *const_names, const double *const_values, const char *const *func1_names, double(*const *funcs1)(void *, double), const char *const *func2_names, double(*const *funcs2)(void *, double, double), void *opaque, int log_offset, void *log_ctx)
Parse and evaluate an expression.
Definition: eval.c:551
int width
width and height of the video frame
Definition: frame.h:179
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
uint8_t log2_chroma_h
Amount to shift the luma height right to find the chroma height.
Definition: pixdesc.h:100
#define AVERROR(e)
Definition: error.h:43
int av_opt_eval_flags(void *obj, const AVOption *o, const char *val, int *flags_out)
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:80
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:148
void * priv
private data for use by the filter
Definition: avfilter.h:277
#define fail()
Definition: checkasm.h:80
int w
New dimensions.
Definition: vf_scale.c:80
static int config_props(AVFilterLink *outlink)
Definition: vf_scale.c:155
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
Definition: rational.c:35
const AVOption * av_opt_find(void *obj, const char *name, const char *unit, int opt_flags, int search_flags)
Look for an option in an object.
Definition: opt.c:756
common internal API header
uint64_t flags
Combination of AV_PIX_FMT_FLAG_...
Definition: pixdesc.h:105
enum AVPixelFormat av_pix_fmt_desc_get_id(const AVPixFmtDescriptor *desc)
Definition: pixdesc.c:1784
static av_cold void uninit(AVFilterContext *ctx)
Definition: vf_scale.c:110
int64_t av_rescale(int64_t a, int64_t b, int64_t c)
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:86
static const AVFilterPad avfilter_vf_scale_outputs[]
Definition: vf_scale.c:325
double param[2]
sws flags
Definition: vf_scale.c:82
#define M_E
Definition: ratecontrol.c:42
#define AV_PIX_FMT_FLAG_PSEUDOPAL
The pixel format is "pseudo-paletted".
Definition: pixdesc.h:156
AVFormatContext * ctx
Definition: movenc.c:48
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
Definition: utils.c:1679
enum AVPixelFormat pix_fmt
Definition: movenc.c:853
char * flags_str
Definition: vf_scale.c:90
LIBAVUTIL_VERSION_INT
Definition: eval.c:55
NULL
Definition: eval.c:55
#define OFFSET(x)
Definition: vf_scale.c:298
void ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
Add *ref as a new reference to formats.
Definition: formats.c:276
AVFilter ff_vf_scale
Definition: vf_scale.c:334
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:158
struct SwsContext * sws
software scaler context
Definition: vf_scale.c:73
av_default_item_name
Definition: dnxhdenc.c:55
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:80
static const AVFilterPad avfilter_vf_scale_inputs[]
Definition: vf_scale.c:316
AVRational sample_aspect_ratio
Sample aspect ratio for the video frame, 0/1 if unknown/unspecified.
Definition: frame.h:206
int sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[], const int srcStride[], int srcSliceY, int srcSliceH, uint8_t *const dst[], const int dstStride[])
Scale the image slice in srcSlice and put the resulting scaled slice in the image in dst...
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(const int16_t *) pi >> 8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(const int32_t *) pi >> 24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(const float *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(const float *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(const float *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(const double *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(const double *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(const double *) pi *(1U<< 31)))) #define SET_CONV_FUNC_GROUP(ofmt, ifmt) static void set_generic_function(AudioConvert *ac) { } void ff_audio_convert_free(AudioConvert **ac) { if(! *ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);} AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, int channels, int sample_rate, int apply_map) { AudioConvert *ac;int in_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) return NULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method !=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt) > 2) { ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc) { av_free(ac);return NULL;} return ac;} in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar) { ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar ? ac->channels :1;} else if(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;else ac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);return ac;} int ff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in) { int use_generic=1;int len=in->nb_samples;int p;if(ac->dc) { av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (dithered)\", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
const char * format
Definition: movenc.c:47
Describe the class of an AVClass context structure.
Definition: log.h:34
Filter definition.
Definition: avfilter.h:120
static const AVFilterPad inputs[]
Definition: af_ashowinfo.c:248
rational number numerator/denominator
Definition: rational.h:43
static av_cold int init(AVFilterContext *ctx)
Definition: vf_scale.c:93
#define M_PHI
Definition: mathematics.h:34
void ff_formats_unref(AVFilterFormats **ref)
If *ref is non-NULL, remove *ref as a reference to the format list it currently points to...
Definition: formats.c:312
const char * name
Filter name.
Definition: avfilter.h:124
int input_is_pal
set to 1 if the input format is paletted
Definition: vf_scale.c:86
static const char *const var_names[]
Definition: vf_scale.c:41
unsigned int flags
Definition: vf_scale.c:81
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:274
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:146
static int filter_frame(AVFilterLink *link, AVFrame *in)
Definition: vf_scale.c:263
#define AV_OPT_SEARCH_FAKE_OBJ
The obj passed to av_opt_find() is fake – only a double pointer to AVClass instead of a required poi...
Definition: opt.h:392
int den
denominator
Definition: rational.h:45
#define SWS_PARAM_DEFAULT
Definition: swscale.h:72
int slice_y
top of current output slice
Definition: vf_scale.c:85
Definition: vf_scale.c:64
int ff_add_format(AVFilterFormats **avff, int fmt)
Add fmt to the list of media formats contained in *avff.
Definition: formats.c:208
#define NAN
Definition: math.h:28
A list of supported formats for one end of a filter link.
Definition: formats.h:64
int sws_isSupportedInput(enum AVPixelFormat pix_fmt)
Return a positive value if pix_fmt is a supported input format, 0 otherwise.
Definition: utils.c:192
An instance of a filter.
Definition: avfilter.h:262
int height
Definition: frame.h:179
FILE * out
Definition: movenc.c:54
const char * av_get_pix_fmt_name(enum AVPixelFormat pix_fmt)
Return the short name for a pixel format, NULL in case pix_fmt is unknown.
Definition: pixdesc.c:1704
internal API functions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:57
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:386
var_name
Definition: setpts.c:61
simple arithmetic expression evaluator
const AVPixFmtDescriptor * av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)
Iterate over all pixel format descriptors known to libavutil.
Definition: pixdesc.c:1775