Hap decoder and encoder

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

1 files changed, 204 insertions, 0 deletions

diff --git a/libavcodec/hapenc.c b/libavcodec/hapenc.c
new file mode 100644
index 0000000000..d828a096d5
--- /dev/null
+++ b/libavcodec/hapenc.c
@@ -0,0 +1,204 @@
+/*
+ * Vidvox Hap encoder
+ * Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com>
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * Hap encoder
+ *
+ * Fourcc: Hap1, Hap5, HapY
+ *
+ * https://github.com/Vidvox/hap/blob/master/documentation/HapVideoDRAFT.md
+ */
+
+#include <stdint.h>
+#include "snappy-c.h"
+
+#include "libavutil/frame.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/opt.h"
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "hap.h"
+#include "internal.h"
+#include "texturedsp.h"
+
+/* A fixed header size allows to skip a memcpy */
+#define HEADER_SIZE 8
+
+static void compress_texture(AVCodecContext *avctx, const AVFrame *f)
+{
+    HapContext *ctx = avctx->priv_data;
+    uint8_t *out = ctx->tex_buf;
+    int i, j;
+
+    for (j = 0; j < avctx->height; j += 4) {
+        for (i = 0; i < avctx->width; i += 4) {
+            uint8_t *p = f->data[0] + i * 4 + j * f->linesize[0];
+            const int step = ctx->tex_fun(out, f->linesize[0], p);
+            out += step;
+        }
+    }
+}
+
+static int hap_encode(AVCodecContext *avctx, AVPacket *pkt,
+                      const AVFrame *frame, int *got_packet)
+{
+    HapContext *ctx = avctx->priv_data;
+    size_t final_size = ctx->max_snappy;
+    int ret, comp = HAP_COMP_SNAPPY;
+    int pktsize = FFMAX(ctx->tex_size, ctx->max_snappy) + HEADER_SIZE;
+
+    /* Allocate maximum size packet, shrink later. */
+    ret = ff_alloc_packet(pkt, pktsize);
+    if (ret < 0)
+        return ret;
+
+    /* DXTC compression. */
+    compress_texture(avctx, frame);
+
+    /* Compress with snappy too, write directly on packet buffer. */
+    ret = snappy_compress(ctx->tex_buf, ctx->tex_size,
+                          pkt->data + HEADER_SIZE, &final_size);
+    if (ret != SNAPPY_OK) {
+        av_log(avctx, AV_LOG_ERROR, "Snappy compress error.\n");
+        return AVERROR_BUG;
+    }
+
+    /* If there is no gain from snappy, just use the raw texture. */
+    if (final_size > ctx->tex_size) {
+        comp = HAP_COMP_NONE;
+        av_log(avctx, AV_LOG_VERBOSE,
+               "Snappy buffer bigger than uncompressed (%lu > %lu bytes).\n",
+               final_size, ctx->tex_size);
+        memcpy(pkt->data + HEADER_SIZE, ctx->tex_buf, ctx->tex_size);
+        final_size = ctx->tex_size;
+    }
+
+    /* Write header at the start. */
+    AV_WL24(pkt->data, 0);
+    AV_WL32(pkt->data + 4, final_size);
+    pkt->data[3] = comp | ctx->section_type;
+
+    av_shrink_packet(pkt, final_size + HEADER_SIZE);
+    pkt->flags |= AV_PKT_FLAG_KEY;
+    *got_packet = 1;
+    return 0;
+}
+
+static av_cold int hap_init(AVCodecContext *avctx)
+{
+    HapContext *ctx = avctx->priv_data;
+    int ratio;
+    int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
+
+    if (ret < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Invalid video size %dx%d.\n",
+               avctx->width, avctx->height);
+        return ret;
+    }
+
+    if (avctx->width % 4 || avctx->height % 4) {
+        av_log(avctx, AV_LOG_ERROR, "Video size %dx%d is not multiple of 4.\n",
+               avctx->width, avctx->height);
+        return AVERROR_INVALIDDATA;
+    }
+
+    ff_texturedspenc_init(&ctx->dxtc);
+
+    switch (ctx->section_type & 0x0F) {
+    case HAP_FMT_RGBDXT1:
+        ratio = 8;
+        avctx->codec_tag = MKTAG('H', 'a', 'p', '1');
+        ctx->tex_fun = ctx->dxtc.dxt1_block;
+        break;
+    case HAP_FMT_RGBADXT5:
+        ratio = 4;
+        avctx->codec_tag = MKTAG('H', 'a', 'p', '5');
+        ctx->tex_fun = ctx->dxtc.dxt5_block;
+        break;
+    case HAP_FMT_YCOCGDXT5:
+        ratio = 4;
+        avctx->codec_tag = MKTAG('H', 'a', 'p', 'Y');
+        ctx->tex_fun = ctx->dxtc.dxt5ys_block;
+        break;
+    default:
+        av_log(avctx, AV_LOG_ERROR, "Invalid format %02X\n", ctx->section_type);
+        return AVERROR_INVALIDDATA;
+    }
+
+    /* Texture compression ratio is constant, so can we computer
+     * beforehand the final size of the uncompressed buffer. */
+    ctx->tex_size   = FFALIGN(avctx->width,  TEXTURE_BLOCK_W) *
+                      FFALIGN(avctx->height, TEXTURE_BLOCK_H) * 4 / ratio;
+    ctx->max_snappy = snappy_max_compressed_length(ctx->tex_size);
+
+    ctx->tex_buf  = av_malloc(ctx->tex_size);
+    if (!ctx->tex_buf)
+        return AVERROR(ENOMEM);
+
+    return 0;
+}
+
+static av_cold int hap_close(AVCodecContext *avctx)
+{
+    HapContext *ctx = avctx->priv_data;
+
+    av_freep(&ctx->tex_buf);
+
+    return 0;
+}
+
+#define OFFSET(x) offsetof(HapContext, x)
+#define FLAGS     AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
+static const AVOption options[] = {
+    { "format", NULL, OFFSET(section_type), AV_OPT_TYPE_INT, { .i64 = HAP_FMT_RGBDXT1 }, HAP_FMT_RGBDXT1, HAP_FMT_YCOCGDXT5, FLAGS, "format" },
+        { "hap",       "Hap 1 (DXT1 textures)", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_FMT_RGBDXT1   }, 0, 0, FLAGS, "format" },
+        { "hap_alpha", "Hap Alpha (DXT5 textures)", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_FMT_RGBADXT5  }, 0, 0, FLAGS, "format" },
+        { "hap_q",     "Hap Q (DXT5-YCoCg textures)", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_FMT_YCOCGDXT5 }, 0, 0, FLAGS, "format" },
+
+    { NULL },
+};
+
+static const AVClass hapenc_class = {
+    .class_name = "Hap encoder",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+AVCodec ff_hap_encoder = {
+    .name           = "hap",
+    .long_name      = NULL_IF_CONFIG_SMALL("Vidvox Hap encoder"),
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_HAP,
+    .priv_data_size = sizeof(HapContext),
+    .priv_class     = &hapenc_class,
+    .init           = hap_init,
+    .encode2        = hap_encode,
+    .close          = hap_close,
+    .pix_fmts       = (const enum AVPixelFormat[]) {
+        AV_PIX_FMT_RGBA, AV_PIX_FMT_NONE,
+    },
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE |
+                      FF_CODEC_CAP_INIT_CLEANUP,
+};