WebP encoder: extract out some methods into a separate helper library.

This is the 2nd patch in preparation for using WebPAnimEncoder API for encoding
and muxing WebP images.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 9 insertions, 270 deletions

diff --git a/libavcodec/libwebpenc.c b/libavcodec/libwebpenc.c
index 95d56ac..6896742 100644
--- a/libavcodec/libwebpenc.c
+++ b/libavcodec/libwebpenc.c
@@ -21,254 +21,29 @@
 
 /**
  * @file
- * WebP encoder using libwebp
+ * WebP encoder using libwebp (WebPEncode API)
  */
 
-#include <webp/encode.h>
+#include "libwebpenc_common.h"
 
-#include "libavutil/common.h"
-#include "libavutil/frame.h"
-#include "libavutil/imgutils.h"
-#include "libavutil/opt.h"
-#include "avcodec.h"
-#include "internal.h"
-
-typedef struct LibWebPContext {
-    AVClass *class;         // class for AVOptions
-    float quality;          // lossy quality 0 - 100
-    int lossless;           // use lossless encoding
-    int preset;             // configuration preset
-    int chroma_warning;     // chroma linesize mismatch warning has been printed
-    int conversion_warning; // pixel format conversion warning has been printed
-    WebPConfig config;      // libwebp configuration
-    AVFrame *ref;
-    int cr_size;
-    int cr_threshold;
-} LibWebPContext;
-
-static int 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;
-}
+typedef LibWebPContextCommon LibWebPContext;
 
 static av_cold int libwebp_encode_init(AVCodecContext *avctx)
 {
-    LibWebPContext *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;
+    return ff_libwebp_encode_init_common(avctx);
 }
 
 static int libwebp_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
                                 const AVFrame *frame, int *got_packet)
 {
     LibWebPContext *s  = avctx->priv_data;
-    AVFrame *alt_frame = NULL;
     WebPPicture *pic = NULL;
+    AVFrame *alt_frame = NULL;
     WebPMemoryWriter mw = { 0 };
-    int ret;
-
-    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 = av_malloc(sizeof(*pic));
-    if (!pic)
-        return AVERROR(ENOMEM);
-
-    ret = WebPPictureInit(pic);
-    if (!ret) {
-        ret = AVERROR_UNKNOWN;
+    int ret = ff_libwebp_get_frame(avctx, s, frame, &alt_frame, &pic);
+    if (ret < 0)
         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 = av_frame_alloc();
-            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 = FF_CEIL_RSHIFT(frame->width , !!p);
-                            int h = FF_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 = FF_CEIL_RSHIFT(frame->width , !!p);
-                                int h = FF_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
-        }
-    }
 
     WebPMemoryWriterInit(&mw);
     pic->custom_ptr = &mw;
@@ -278,7 +53,7 @@ static int libwebp_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
     if (!ret) {
         av_log(avctx, AV_LOG_ERROR, "WebPEncode() failed with error: %d\n",
                pic->error_code);
-        ret = libwebp_error_to_averror(pic->error_code);
+        ret = ff_libwebp_error_to_averror(pic->error_code);
         goto end;
     }
 
@@ -305,45 +80,9 @@ end:
 
 static int libwebp_encode_close(AVCodecContext *avctx)
 {
-    LibWebPContext *s  = avctx->priv_data;
-
-    av_frame_free(&s->ref);
-
-    return 0;
+    return ff_libwebp_encode_close_common(avctx);
 }
 
-#define OFFSET(x) offsetof(LibWebPContext, x)
-#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
-static const AVOption options[] = {
-    { "lossless",   "Use lossless mode",       OFFSET(lossless), AV_OPT_TYPE_INT,   { .i64 =  0 },  0, 1,                           VE           },
-    { "preset",     "Configuration preset",    OFFSET(preset),   AV_OPT_TYPE_INT,   { .i64 = -1 }, -1, WEBP_PRESET_TEXT,            VE, "preset" },
-    { "none",       "do not use a preset",                              0, AV_OPT_TYPE_CONST, { .i64 = -1                  }, 0, 0, VE, "preset" },
-    { "default",    "default preset",                                   0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_DEFAULT }, 0, 0, VE, "preset" },
-    { "picture",    "digital picture, like portrait, inner shot",       0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_PICTURE }, 0, 0, VE, "preset" },
-    { "photo",      "outdoor photograph, with natural lighting",        0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_PHOTO   }, 0, 0, VE, "preset" },
-    { "drawing",    "hand or line drawing, with high-contrast details", 0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_DRAWING }, 0, 0, VE, "preset" },
-    { "icon",       "small-sized colorful images",                      0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_ICON    }, 0, 0, VE, "preset" },
-    { "text",       "text-like",                                        0, AV_OPT_TYPE_CONST, { .i64 = WEBP_PRESET_TEXT    }, 0, 0, VE, "preset" },
-    { "cr_threshold","Conditional replenishment threshold",     OFFSET(cr_threshold), AV_OPT_TYPE_INT, { .i64 =  0  },  0, INT_MAX, VE           },
-    { "cr_size"     ,"Conditional replenishment block size",    OFFSET(cr_size)     , AV_OPT_TYPE_INT, { .i64 =  16 },  0, 256,     VE           },
-    { "quality"     ,"Quality",                OFFSET(quality),  AV_OPT_TYPE_FLOAT, { .dbl =  75 }, 0, 100,                         VE           },
-    { NULL },
-};
-
-
-static const AVClass class = {
-    .class_name = "libwebp",
-    .item_name  = av_default_item_name,
-    .option     = options,
-    .version    = LIBAVUTIL_VERSION_INT,
-};
-
-static const AVCodecDefault libwebp_defaults[] = {
-    { "compression_level",  "4"  },
-    { "global_quality",     "-1" },
-    { NULL },
-};
-
 AVCodec ff_libwebp_encoder = {
     .name           = "libwebp",
     .long_name      = NULL_IF_CONFIG_SMALL("libwebp WebP image"),