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
ff_libwebp_error_to_averror(int err)29 int ff_libwebp_error_to_averror(int err)
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
ff_libwebp_encode_init_common(AVCodecContext * avctx)43 av_cold int ff_libwebp_encode_init_common(AVCodecContext *avctx)
44 {
45 LibWebPContextCommon *s = avctx->priv_data;
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
ff_libwebp_get_frame(AVCodecContext * avctx,LibWebPContextCommon * s,const AVFrame * frame,AVFrame ** alt_frame_ptr,WebPPicture ** pic_ptr)86 int ff_libwebp_get_frame(AVCodecContext *avctx, LibWebPContextCommon *s,
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, 0);
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 }
255