/*
* WebP encoding support via libwebp
* Copyright (c) 2013 Justin Ruggles <justin.ruggles@gmail.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* WebP encoder using libwebp: common structs and methods.
*/
#include "libwebpenc_common.h"
int ff_libwebp_error_to_averror(int err)
{
switch (err) {
case VP8_ENC_ERROR_OUT_OF_MEMORY:
case VP8_ENC_ERROR_BITSTREAM_OUT_OF_MEMORY:
return AVERROR(ENOMEM);
case VP8_ENC_ERROR_NULL_PARAMETER:
case VP8_ENC_ERROR_INVALID_CONFIGURATION:
case VP8_ENC_ERROR_BAD_DIMENSION:
return AVERROR(EINVAL);
}
return AVERROR_UNKNOWN;
}
av_cold int ff_libwebp_encode_init_common(AVCodecContext *avctx)
{
LibWebPContextCommon *s = avctx->priv_data;
int ret;
if (avctx->global_quality >= 0)
s->quality = av_clipf(avctx->global_quality / (float)FF_QP2LAMBDA,
0.0f, 100.0f);
if (avctx->compression_level < 0 || avctx->compression_level > 6) {
av_log(avctx, AV_LOG_WARNING, "invalid compression level: %d\n",
avctx->compression_level);
avctx->compression_level = av_clip(avctx->compression_level, 0, 6);
}
if (s->preset >= WEBP_PRESET_DEFAULT) {
ret = WebPConfigPreset(&s->config, s->preset, s->quality);
if (!ret)
return AVERROR_UNKNOWN;
s->lossless = s->config.lossless;
s->quality = s->config.quality;
avctx->compression_level = s->config.method;
} else {
ret = WebPConfigInit(&s->config);
if (!ret)
return AVERROR_UNKNOWN;
s->config.lossless = s->lossless;
s->config.quality = s->quality;
s->config.method = avctx->compression_level;
ret = WebPValidateConfig(&s->config);
if (!ret)
return AVERROR(EINVAL);
}
av_log(avctx, AV_LOG_DEBUG, "%s - quality=%.1f method=%d\n",
s->lossless ? "Lossless" : "Lossy", s->quality,
avctx->compression_level);
return 0;
}
int ff_libwebp_get_frame(AVCodecContext *avctx, LibWebPContextCommon *s,
const AVFrame *frame, AVFrame **alt_frame_ptr,
WebPPicture **pic_ptr) {
int ret;
WebPPicture *pic = NULL;
AVFrame *alt_frame = NULL;
if (avctx->width > WEBP_MAX_DIMENSION || avctx->height > WEBP_MAX_DIMENSION) {
av_log(avctx, AV_LOG_ERROR, "Picture size is too large. Max is %dx%d.\n",
WEBP_MAX_DIMENSION, WEBP_MAX_DIMENSION);
return AVERROR(EINVAL);
}
*pic_ptr = av_malloc(sizeof(*pic));
pic = *pic_ptr;
if (!pic)
return AVERROR(ENOMEM);
ret = WebPPictureInit(pic);
if (!ret) {
ret = AVERROR_UNKNOWN;
goto end;
}
pic->width = avctx->width;
pic->height = avctx->height;
if (avctx->pix_fmt == AV_PIX_FMT_RGB32) {
if (!s->lossless) {
/* libwebp will automatically convert RGB input to YUV when
encoding lossy. */
if (!s->conversion_warning) {
av_log(avctx, AV_LOG_WARNING,
"Using libwebp for RGB-to-YUV conversion. You may want "
"to consider passing in YUV instead for lossy "
"encoding.\n");
s->conversion_warning = 1;
}
}
pic->use_argb = 1;
pic->argb = (uint32_t *)frame->data[0];
pic->argb_stride = frame->linesize[0] / 4;
} else {
if (frame->linesize[1] != frame->linesize[2] || s->cr_threshold) {
if (!s->chroma_warning && !s->cr_threshold) {
av_log(avctx, AV_LOG_WARNING,
"Copying frame due to differing chroma linesizes.\n");
s->chroma_warning = 1;
}
*alt_frame_ptr = av_frame_alloc();
alt_frame = *alt_frame_ptr;
if (!alt_frame) {
ret = AVERROR(ENOMEM);
goto end;
}
alt_frame->width = frame->width;
alt_frame->height = frame->height;
alt_frame->format = frame->format;
if (s->cr_threshold)
alt_frame->format = AV_PIX_FMT_YUVA420P;
ret = av_frame_get_buffer(alt_frame, 32);
if (ret < 0)
goto end;
alt_frame->format = frame->format;
av_frame_copy(alt_frame, frame);
frame = alt_frame;
if (s->cr_threshold) {
int x,y, x2, y2, p;
int bs = s->cr_size;
if (!s->ref) {
s->ref = av_frame_clone(frame);
if (!s->ref) {
ret = AVERROR(ENOMEM);
goto end;
}
}
alt_frame->format = AV_PIX_FMT_YUVA420P;
for (y = 0; y < frame->height; y+= bs) {
for (x = 0; x < frame->width; x+= bs) {
int skip;
int sse = 0;
for (p = 0; p < 3; p++) {
int bs2 = bs >> !!p;
int w = AV_CEIL_RSHIFT(frame->width , !!p);
int h = AV_CEIL_RSHIFT(frame->height, !!p);
int xs = x >> !!p;
int ys = y >> !!p;
for (y2 = ys; y2 < FFMIN(ys + bs2, h); y2++) {
for (x2 = xs; x2 < FFMIN(xs + bs2, w); x2++) {
int diff = frame->data[p][frame->linesize[p] * y2 + x2]
-s->ref->data[p][frame->linesize[p] * y2 + x2];
sse += diff*diff;
}
}
}
skip = sse < s->cr_threshold && frame->data[3] != s->ref->data[3];
if (!skip)
for (p = 0; p < 3; p++) {
int bs2 = bs >> !!p;
int w = AV_CEIL_RSHIFT(frame->width , !!p);
int h = AV_CEIL_RSHIFT(frame->height, !!p);
int xs = x >> !!p;
int ys = y >> !!p;
for (y2 = ys; y2 < FFMIN(ys + bs2, h); y2++) {
memcpy(&s->ref->data[p][frame->linesize[p] * y2 + xs],
& frame->data[p][frame->linesize[p] * y2 + xs], FFMIN(bs2, w-xs));
}
}
for (y2 = y; y2 < FFMIN(y+bs, frame->height); y2++) {
memset(&frame->data[3][frame->linesize[3] * y2 + x],
skip ? 0 : 255,
FFMIN(bs, frame->width-x));
}
}
}
}
}
pic->use_argb = 0;
pic->y = frame->data[0];
pic->u = frame->data[1];
pic->v = frame->data[2];
pic->y_stride = frame->linesize[0];
pic->uv_stride = frame->linesize[1];
if (frame->format == AV_PIX_FMT_YUVA420P) {
pic->colorspace = WEBP_YUV420A;
pic->a = frame->data[3];
pic->a_stride = frame->linesize[3];
if (alt_frame)
WebPCleanupTransparentArea(pic);
} else {
pic->colorspace = WEBP_YUV420;
}
if (s->lossless) {
/* We do not have a way to automatically prioritize RGB over YUV
in automatic pixel format conversion based on whether we're
encoding lossless or lossy, so we do conversion with libwebp as
a convenience. */
if (!s->conversion_warning) {
av_log(avctx, AV_LOG_WARNING,
"Using libwebp for YUV-to-RGB conversion. You may want "
"to consider passing in RGB instead for lossless "
"encoding.\n");
s->conversion_warning = 1;
}
#if (WEBP_ENCODER_ABI_VERSION <= 0x201)
/* libwebp should do the conversion automatically, but there is a
bug that causes it to return an error instead, so a work-around
is required.
See https://code.google.com/p/webp/issues/detail?id=178 */
pic->memory_ = (void*)1; /* something non-null */
ret = WebPPictureYUVAToARGB(pic);
if (!ret) {
av_log(avctx, AV_LOG_ERROR,
"WebPPictureYUVAToARGB() failed with error: %d\n",
pic->error_code);
ret = libwebp_error_to_averror(pic->error_code);
goto end;
}
pic->memory_ = NULL; /* restore pointer */
#endif
}
}
end:
return ret;
}