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libwebpenc_common.c
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1 /*
2  * WebP encoding support via libwebp
3  * Copyright (c) 2013 Justin Ruggles <justin.ruggles@gmail.com>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * WebP encoder using libwebp: common structs and methods.
25  */
26 
27 #include "libwebpenc_common.h"
28 
30 {
31  switch (err) {
32  case VP8_ENC_ERROR_OUT_OF_MEMORY:
33  case VP8_ENC_ERROR_BITSTREAM_OUT_OF_MEMORY:
34  return AVERROR(ENOMEM);
35  case VP8_ENC_ERROR_NULL_PARAMETER:
36  case VP8_ENC_ERROR_INVALID_CONFIGURATION:
37  case VP8_ENC_ERROR_BAD_DIMENSION:
38  return AVERROR(EINVAL);
39  }
40  return AVERROR_UNKNOWN;
41 }
42 
44 {
46  int ret;
47 
48  if (avctx->global_quality >= 0)
49  s->quality = av_clipf(avctx->global_quality / (float)FF_QP2LAMBDA,
50  0.0f, 100.0f);
51 
52  if (avctx->compression_level < 0 || avctx->compression_level > 6) {
53  av_log(avctx, AV_LOG_WARNING, "invalid compression level: %d\n",
54  avctx->compression_level);
55  avctx->compression_level = av_clip(avctx->compression_level, 0, 6);
56  }
57 
58  if (s->preset >= WEBP_PRESET_DEFAULT) {
59  ret = WebPConfigPreset(&s->config, s->preset, s->quality);
60  if (!ret)
61  return AVERROR_UNKNOWN;
62  s->lossless = s->config.lossless;
63  s->quality = s->config.quality;
64  avctx->compression_level = s->config.method;
65  } else {
66  ret = WebPConfigInit(&s->config);
67  if (!ret)
68  return AVERROR_UNKNOWN;
69 
70  s->config.lossless = s->lossless;
71  s->config.quality = s->quality;
72  s->config.method = avctx->compression_level;
73 
74  ret = WebPValidateConfig(&s->config);
75  if (!ret)
76  return AVERROR(EINVAL);
77  }
78 
79  av_log(avctx, AV_LOG_DEBUG, "%s - quality=%.1f method=%d\n",
80  s->lossless ? "Lossless" : "Lossy", s->quality,
81  avctx->compression_level);
82 
83  return 0;
84 }
85 
87  const AVFrame *frame, AVFrame **alt_frame_ptr,
88  WebPPicture **pic_ptr) {
89  int ret;
90  WebPPicture *pic = NULL;
91  AVFrame *alt_frame = NULL;
92 
93  if (avctx->width > WEBP_MAX_DIMENSION || avctx->height > WEBP_MAX_DIMENSION) {
94  av_log(avctx, AV_LOG_ERROR, "Picture size is too large. Max is %dx%d.\n",
95  WEBP_MAX_DIMENSION, WEBP_MAX_DIMENSION);
96  return AVERROR(EINVAL);
97  }
98 
99  *pic_ptr = av_malloc(sizeof(*pic));
100  pic = *pic_ptr;
101  if (!pic)
102  return AVERROR(ENOMEM);
103 
104  ret = WebPPictureInit(pic);
105  if (!ret) {
106  ret = AVERROR_UNKNOWN;
107  goto end;
108  }
109  pic->width = avctx->width;
110  pic->height = avctx->height;
111 
112  if (avctx->pix_fmt == AV_PIX_FMT_RGB32) {
113  if (!s->lossless) {
114  /* libwebp will automatically convert RGB input to YUV when
115  encoding lossy. */
116  if (!s->conversion_warning) {
117  av_log(avctx, AV_LOG_WARNING,
118  "Using libwebp for RGB-to-YUV conversion. You may want "
119  "to consider passing in YUV instead for lossy "
120  "encoding.\n");
121  s->conversion_warning = 1;
122  }
123  }
124  pic->use_argb = 1;
125  pic->argb = (uint32_t *)frame->data[0];
126  pic->argb_stride = frame->linesize[0] / 4;
127  } else {
128  if (frame->linesize[1] != frame->linesize[2] || s->cr_threshold) {
129  if (!s->chroma_warning && !s->cr_threshold) {
130  av_log(avctx, AV_LOG_WARNING,
131  "Copying frame due to differing chroma linesizes.\n");
132  s->chroma_warning = 1;
133  }
134  *alt_frame_ptr = av_frame_alloc();
135  alt_frame = *alt_frame_ptr;
136  if (!alt_frame) {
137  ret = AVERROR(ENOMEM);
138  goto end;
139  }
140  alt_frame->width = frame->width;
141  alt_frame->height = frame->height;
142  alt_frame->format = frame->format;
143  if (s->cr_threshold)
144  alt_frame->format = AV_PIX_FMT_YUVA420P;
145  ret = av_frame_get_buffer(alt_frame, 32);
146  if (ret < 0)
147  goto end;
148  alt_frame->format = frame->format;
149  av_frame_copy(alt_frame, frame);
150  frame = alt_frame;
151  if (s->cr_threshold) {
152  int x,y, x2, y2, p;
153  int bs = s->cr_size;
154 
155  if (!s->ref) {
156  s->ref = av_frame_clone(frame);
157  if (!s->ref) {
158  ret = AVERROR(ENOMEM);
159  goto end;
160  }
161  }
162 
163  alt_frame->format = AV_PIX_FMT_YUVA420P;
164  for (y = 0; y < frame->height; y+= bs) {
165  for (x = 0; x < frame->width; x+= bs) {
166  int skip;
167  int sse = 0;
168  for (p = 0; p < 3; p++) {
169  int bs2 = bs >> !!p;
170  int w = AV_CEIL_RSHIFT(frame->width , !!p);
171  int h = AV_CEIL_RSHIFT(frame->height, !!p);
172  int xs = x >> !!p;
173  int ys = y >> !!p;
174  for (y2 = ys; y2 < FFMIN(ys + bs2, h); y2++) {
175  for (x2 = xs; x2 < FFMIN(xs + bs2, w); x2++) {
176  int diff = frame->data[p][frame->linesize[p] * y2 + x2]
177  -s->ref->data[p][frame->linesize[p] * y2 + x2];
178  sse += diff*diff;
179  }
180  }
181  }
182  skip = sse < s->cr_threshold && frame->data[3] != s->ref->data[3];
183  if (!skip)
184  for (p = 0; p < 3; p++) {
185  int bs2 = bs >> !!p;
186  int w = AV_CEIL_RSHIFT(frame->width , !!p);
187  int h = AV_CEIL_RSHIFT(frame->height, !!p);
188  int xs = x >> !!p;
189  int ys = y >> !!p;
190  for (y2 = ys; y2 < FFMIN(ys + bs2, h); y2++) {
191  memcpy(&s->ref->data[p][frame->linesize[p] * y2 + xs],
192  & frame->data[p][frame->linesize[p] * y2 + xs], FFMIN(bs2, w-xs));
193  }
194  }
195  for (y2 = y; y2 < FFMIN(y+bs, frame->height); y2++) {
196  memset(&frame->data[3][frame->linesize[3] * y2 + x],
197  skip ? 0 : 255,
198  FFMIN(bs, frame->width-x));
199  }
200  }
201  }
202  }
203  }
204 
205  pic->use_argb = 0;
206  pic->y = frame->data[0];
207  pic->u = frame->data[1];
208  pic->v = frame->data[2];
209  pic->y_stride = frame->linesize[0];
210  pic->uv_stride = frame->linesize[1];
211  if (frame->format == AV_PIX_FMT_YUVA420P) {
212  pic->colorspace = WEBP_YUV420A;
213  pic->a = frame->data[3];
214  pic->a_stride = frame->linesize[3];
215  if (alt_frame)
216  WebPCleanupTransparentArea(pic);
217  } else {
218  pic->colorspace = WEBP_YUV420;
219  }
220 
221  if (s->lossless) {
222  /* We do not have a way to automatically prioritize RGB over YUV
223  in automatic pixel format conversion based on whether we're
224  encoding lossless or lossy, so we do conversion with libwebp as
225  a convenience. */
226  if (!s->conversion_warning) {
227  av_log(avctx, AV_LOG_WARNING,
228  "Using libwebp for YUV-to-RGB conversion. You may want "
229  "to consider passing in RGB instead for lossless "
230  "encoding.\n");
231  s->conversion_warning = 1;
232  }
233 
234 #if (WEBP_ENCODER_ABI_VERSION <= 0x201)
235  /* libwebp should do the conversion automatically, but there is a
236  bug that causes it to return an error instead, so a work-around
237  is required.
238  See https://code.google.com/p/webp/issues/detail?id=178 */
239  pic->memory_ = (void*)1; /* something non-null */
240  ret = WebPPictureYUVAToARGB(pic);
241  if (!ret) {
242  av_log(avctx, AV_LOG_ERROR,
243  "WebPPictureYUVAToARGB() failed with error: %d\n",
244  pic->error_code);
245  ret = libwebp_error_to_averror(pic->error_code);
246  goto end;
247  }
248  pic->memory_ = NULL; /* restore pointer */
249 #endif
250  }
251  }
252 end:
253  return ret;
254 }
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
This structure describes decoded (raw) audio or video data.
Definition: frame.h:201
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1697
static int sse(MpegEncContext *s, uint8_t *src1, uint8_t *src2, int w, int h, int stride)
planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
Definition: pixfmt.h:97
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:150
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
static AVFrame * frame
#define av_log(a,...)
int width
Definition: frame.h:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
WebP encoder using libwebp: common structs and methods.
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
int ff_libwebp_get_frame(AVCodecContext *avctx, LibWebPContextCommon *s, const AVFrame *frame, AVFrame **alt_frame_ptr, WebPPicture **pic_ptr)
av_cold int ff_libwebp_encode_init_common(AVCodecContext *avctx)
int av_frame_copy(AVFrame *dst, const AVFrame *src)
Copy the frame data from src to dst.
Definition: frame.c:746
#define FFMIN(a, b)
Definition: common.h:96
int width
picture width / height.
Definition: avcodec.h:1660
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:497
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:274
int ff_libwebp_error_to_averror(int err)
int compression_level
Definition: avcodec.h:1560
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:232
main external API structure.
Definition: avcodec.h:1488
#define AV_PIX_FMT_RGB32
Definition: pixfmt.h:342
int av_frame_get_buffer(AVFrame *frame, int align)
Allocate new buffer(s) for audio or video data.
Definition: frame.c:283
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:1554
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:215
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
void * priv_data
Definition: avcodec.h:1515
static av_always_inline int diff(const uint32_t a, const uint32_t b)
#define FF_QP2LAMBDA
factor to convert from H.263 QP to lambda
Definition: avutil.h:227
int height
Definition: frame.h:259
#define AV_CEIL_RSHIFT(a, b)
Definition: common.h:58