git.sesse.net Git - ffmpeg/blob - libavcodec/libwebpenc_common.c

   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
  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
  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
  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, 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 }