FFmpeg  4.0
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 
49 static int config_input(AVFilterLink *inlink)
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 
87 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
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
const char * s
Definition: avisynth_c.h:768
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:218
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)
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:679
int h
Definition: vf_qp.c:35
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: vf_qp.c:87
int stride
Definition: mace.c:144
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:1080
static const AVFilterPad qp_outputs[]
Definition: vf_qp.c:167
AVOptions.
Definition: eval.c:157
static int flags
Definition: log.c:55
#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:744
int evaluate_per_mb
Definition: vf_qp.c:36
#define AVERROR(e)
Definition: error.h:43
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:116
#define NAN
Definition: mathematics.h:64
AVFormatContext * ctx
Definition: movenc.c:48
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:538
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:334
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
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
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
cl_device_type type
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
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:734
An instance of a filter.
Definition: avfilter.h:338
FILE * out
Definition: movenc.c:54
internal API functions
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