FFmpeg
vf_qp.c
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1 /*
2  * Copyright (C) 2004 Michael Niedermayer <michaelni@gmx.at>
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 #include <math.h>
22 #include "libavutil/eval.h"
23 #include "libavutil/imgutils.h"
24 #include "libavutil/pixdesc.h"
25 #include "libavutil/opt.h"
26 #include "avfilter.h"
27 #include "formats.h"
28 #include "internal.h"
29 #include "video.h"
30 
31 typedef struct QPContext {
32  const AVClass *class;
33  char *qp_expr_str;
34  int8_t lut[257];
35  int h, qstride;
37 } QPContext;
38 
39 #define OFFSET(x) offsetof(QPContext, x)
40 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
41 
42 static const AVOption qp_options[] = {
43  { "qp", "set qp expression", OFFSET(qp_expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
44  { NULL }
45 };
46 
48 
50 {
51  AVFilterContext *ctx = inlink->dst;
52  QPContext *s = ctx->priv;
53  int i;
54  int ret;
55  AVExpr *e = NULL;
56  static const char *var_names[] = { "known", "qp", "x", "y", "w", "h", NULL };
57 
58  if (!s->qp_expr_str)
59  return 0;
60 
61  ret = av_expr_parse(&e, s->qp_expr_str, var_names, NULL, NULL, NULL, NULL, 0, ctx);
62  if (ret < 0)
63  return ret;
64 
65  s->h = (inlink->h + 15) >> 4;
66  s->qstride = (inlink->w + 15) >> 4;
67  for (i = -129; i < 128; i++) {
68  double var_values[] = { i != -129, i, NAN, NAN, s->qstride, s->h, 0};
69  double temp_val = av_expr_eval(e, var_values, NULL);
70 
71  if (isnan(temp_val)) {
72  if(strchr(s->qp_expr_str, 'x') || strchr(s->qp_expr_str, 'y'))
73  s->evaluate_per_mb = 1;
74  else {
75  av_expr_free(e);
76  return AVERROR(EINVAL);
77  }
78  }
79 
80  s->lut[i + 129] = lrintf(temp_val);
81  }
82  av_expr_free(e);
83 
84  return 0;
85 }
86 
88 {
89  AVFilterContext *ctx = inlink->dst;
90  AVFilterLink *outlink = ctx->outputs[0];
91  QPContext *s = ctx->priv;
92  AVBufferRef *out_qp_table_buf;
93  AVFrame *out = NULL;
94  const int8_t *in_qp_table;
95  int type, stride, ret;
96 
97  if (!s->qp_expr_str || ctx->is_disabled)
98  return ff_filter_frame(outlink, in);
99 
100  out_qp_table_buf = av_buffer_alloc(s->h * s->qstride);
101  if (!out_qp_table_buf) {
102  ret = AVERROR(ENOMEM);
103  goto fail;
104  }
105 
106  out = av_frame_clone(in);
107  if (!out) {
108  av_buffer_unref(&out_qp_table_buf);
109  ret = AVERROR(ENOMEM);
110  goto fail;
111  }
112 
113  in_qp_table = av_frame_get_qp_table(in, &stride, &type);
114  av_frame_set_qp_table(out, out_qp_table_buf, s->qstride, type);
115 
116 
117  if (s->evaluate_per_mb) {
118  int y, x;
119 
120  for (y = 0; y < s->h; y++)
121  for (x = 0; x < s->qstride; x++) {
122  int qp = in_qp_table ? in_qp_table[x + stride * y] : NAN;
123  double var_values[] = { !!in_qp_table, qp, x, y, s->qstride, s->h, 0};
124  static const char *var_names[] = { "known", "qp", "x", "y", "w", "h", NULL };
125  double temp_val;
126 
127  ret = av_expr_parse_and_eval(&temp_val, s->qp_expr_str,
128  var_names, var_values,
129  NULL, NULL, NULL, NULL, 0, 0, ctx);
130  if (ret < 0)
131  goto fail;
132  out_qp_table_buf->data[x + s->qstride * y] = lrintf(temp_val);
133  }
134  } else if (in_qp_table) {
135  int y, x;
136 
137  for (y = 0; y < s->h; y++)
138  for (x = 0; x < s->qstride; x++)
139  out_qp_table_buf->data[x + s->qstride * y] = s->lut[129 +
140  ((int8_t)in_qp_table[x + stride * y])];
141  } else {
142  int y, x, qp = s->lut[0];
143 
144  for (y = 0; y < s->h; y++)
145  for (x = 0; x < s->qstride; x++)
146  out_qp_table_buf->data[x + s->qstride * y] = qp;
147  }
148 
149  ret = ff_filter_frame(outlink, out);
150  out = NULL;
151 fail:
152  av_frame_free(&in);
153  av_frame_free(&out);
154  return ret;
155 }
156 
157 static const AVFilterPad qp_inputs[] = {
158  {
159  .name = "default",
160  .type = AVMEDIA_TYPE_VIDEO,
161  .filter_frame = filter_frame,
162  .config_props = config_input,
163  },
164  { NULL }
165 };
166 
167 static const AVFilterPad qp_outputs[] = {
168  {
169  .name = "default",
170  .type = AVMEDIA_TYPE_VIDEO,
171  },
172  { NULL }
173 };
174 
176  .name = "qp",
177  .description = NULL_IF_CONFIG_SMALL("Change video quantization parameters."),
178  .priv_size = sizeof(QPContext),
179  .inputs = qp_inputs,
180  .outputs = qp_outputs,
181  .priv_class = &qp_class,
183 };
int av_frame_set_qp_table(AVFrame *f, AVBufferRef *buf, int stride, int qp_type)
Definition: frame.c:54
#define NULL
Definition: coverity.c:32
void av_buffer_unref(AVBufferRef **buf)
Free a given reference and automatically free the buffer if there are no more references to it...
Definition: buffer.c:125
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
misc image utilities
Main libavfilter public API header.
AVFilter ff_vf_qp
Definition: vf_qp.c:175
AVFILTER_DEFINE_CLASS(qp)
GLint GLenum type
Definition: opengl_enc.c:104
static int config_input(AVFilterLink *inlink)
Definition: vf_qp.c:49
int av_expr_parse(AVExpr **expr, const char *s, const char *const *const_names, const char *const *func1_names, double(*const *funcs1)(void *, double), const char *const *func2_names, double(*const *funcs2)(void *, double, double), int log_offset, void *log_ctx)
Parse an expression.
Definition: eval.c:683
int h
Definition: vf_qp.c:35
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: vf_qp.c:87
char * qp_expr_str
Definition: vf_qp.c:33
int is_disabled
the enabled state from the last expression evaluation
Definition: avfilter.h:385
const char * name
Pad name.
Definition: internal.h:60
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1093
static const AVFilterPad qp_outputs[]
Definition: vf_qp.c:167
AVOptions.
Definition: eval.c:157
#define lrintf(x)
Definition: libm_mips.h:70
static const char *const var_names[]
Definition: aeval.c:36
A filter pad used for either input or output.
Definition: internal.h:54
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:748
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
int evaluate_per_mb
Definition: vf_qp.c:36
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
static const AVFilterPad qp_inputs[]
Definition: vf_qp.c:157
#define fail()
Definition: checkasm.h:122
#define NAN
Definition: mathematics.h:64
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:540
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
void av_expr_free(AVExpr *e)
Free a parsed expression previously created with av_expr_parse().
Definition: eval.c:336
AVBufferRef * av_buffer_alloc(int size)
Allocate an AVBuffer of the given size using av_malloc().
Definition: buffer.c:67
uint8_t * data
The data buffer.
Definition: buffer.h:89
static const AVOption qp_options[]
Definition: vf_qp.c:42
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
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)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
#define isnan(x)
Definition: libm.h:340
const char * name
Filter name.
Definition: avfilter.h:148
#define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL
Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will have its filter_frame() c...
Definition: avfilter.h:133
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
#define flags(name, subs,...)
Definition: cbs_av1.c:561
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
A reference to a data buffer.
Definition: buffer.h:81
#define FLAGS
Definition: vf_qp.c:40
int qstride
Definition: vf_qp.c:35
int8_t lut[257]
Definition: vf_qp.c:34
double av_expr_eval(AVExpr *e, const double *const_values, void *opaque)
Evaluate a previously parsed expression.
Definition: eval.c:738
An instance of a filter.
Definition: avfilter.h:338
FILE * out
Definition: movenc.c:54
#define stride
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
int8_t * av_frame_get_qp_table(AVFrame *f, int *stride, int *type)
Definition: frame.c:90
#define OFFSET(x)
Definition: vf_qp.c:39
simple arithmetic expression evaluator