Hap decoder and encoder

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

1 files changed, 238 insertions, 0 deletions

diff --git a/libavcodec/hapdec.c b/libavcodec/hapdec.c
new file mode 100644
index 0000000000..72db9f4702
--- /dev/null
+++ b/libavcodec/hapdec.c
@@ -0,0 +1,238 @@
+/*
+ * Vidvox Hap decoder
+ * 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 decoder
+ *
+ * Fourcc: Hap1, Hap5, HapY
+ *
+ * https://github.com/Vidvox/hap/blob/master/documentation/HapVideoDRAFT.md
+ */
+
+#include <stdint.h>
+
+#include "libavutil/imgutils.h"
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "hap.h"
+#include "internal.h"
+#include "snappy.h"
+#include "texturedsp.h"
+#include "thread.h"
+
+/* The first three bytes are the size of the section past the header, or zero
+ * if the length is stored in the next long word. The fourth byte in the first
+ * long word indicates the type of the current section. */
+static int parse_section_header(AVCodecContext *avctx)
+{
+    HapContext *ctx = avctx->priv_data;
+    GetByteContext *gbc = &ctx->gbc;
+    int length;
+
+    if (bytestream2_get_bytes_left(gbc) < 4)
+        return AVERROR_INVALIDDATA;
+
+    length = bytestream2_get_le24(gbc);
+
+    ctx->section_type = bytestream2_get_byte(gbc);
+
+    if (length == 0) {
+        if (bytestream2_get_bytes_left(gbc) < 4)
+            return AVERROR_INVALIDDATA;
+        length = bytestream2_get_le32(gbc);
+    }
+
+    if (length > bytestream2_get_bytes_left(gbc) || length == 0)
+        return AVERROR_INVALIDDATA;
+
+    return length;
+}
+
+/* Prepare the texture to be decompressed */
+static int setup_texture(AVCodecContext *avctx, size_t length)
+{
+    HapContext *ctx = avctx->priv_data;
+    GetByteContext *gbc = &ctx->gbc;
+    int64_t snappy_size;
+    const char *texture_name;
+    const char *compressorstr;
+    int ret;
+
+    switch (ctx->section_type & 0x0F) {
+    case HAP_FMT_RGBDXT1:
+        ctx->tex_rat = 8;
+        ctx->tex_fun = ctx->dxtc.dxt1_block;
+        texture_name = "DXT1";
+        break;
+    case HAP_FMT_RGBADXT5:
+        ctx->tex_rat = 16;
+        ctx->tex_fun = ctx->dxtc.dxt5_block;
+        texture_name = "DXT5";
+        break;
+    case HAP_FMT_YCOCGDXT5:
+        ctx->tex_rat = 16;
+        ctx->tex_fun = ctx->dxtc.dxt5ys_block;
+        texture_name = "DXT5-YCoCg-scaled";
+        break;
+    default:
+        av_log(avctx, AV_LOG_ERROR,
+               "Invalid format mode %02X.\n", ctx->section_type);
+        return AVERROR_INVALIDDATA;
+    }
+
+    switch (ctx->section_type & 0xF0) {
+    case HAP_COMP_NONE:
+        /* Only DXTC texture compression */
+        ctx->tex_data = gbc->buffer;
+        ctx->tex_size = length;
+        compressorstr = "none";
+        break;
+    case HAP_COMP_SNAPPY:
+        /* Uncompress the frame */
+        ret = ff_snappy_uncompress(gbc, &ctx->snappied, &snappy_size);
+        if (ret < 0) {
+             av_log(avctx, AV_LOG_ERROR, "Snappy uncompress error\n");
+             return ret;
+        }
+
+        ctx->tex_data = ctx->snappied;
+        ctx->tex_size = snappy_size;
+        compressorstr = "snappy";
+        break;
+    case HAP_COMP_COMPLEX:
+        compressorstr = "complex";
+        avpriv_request_sample(avctx, "Complex Hap compressor");
+        return AVERROR_PATCHWELCOME;
+        break;
+    default:
+        av_log(avctx, AV_LOG_ERROR,
+               "Invalid compressor mode %02X.\n", ctx->section_type);
+        return AVERROR_INVALIDDATA;
+    }
+
+    av_log(avctx, AV_LOG_DEBUG, "%s texture with %s compressor\n",
+           texture_name, compressorstr);
+
+    return 0;
+}
+
+static int decompress_texture_thread(AVCodecContext *avctx, void *arg,
+                                     int block_nb, int thread_nb)
+{
+    HapContext *ctx = avctx->priv_data;
+    AVFrame *frame = arg;
+    int x = (TEXTURE_BLOCK_W * block_nb) % avctx->coded_width;
+    int y = TEXTURE_BLOCK_H * (TEXTURE_BLOCK_W * block_nb / avctx->coded_width);
+    uint8_t *p = frame->data[0] + x * 4 + y * frame->linesize[0];
+    const uint8_t *d = ctx->tex_data + block_nb * ctx->tex_rat;
+
+    ctx->tex_fun(p, frame->linesize[0], d);
+    return 0;
+}
+
+static int hap_decode(AVCodecContext *avctx, void *data,
+                      int *got_frame, AVPacket *avpkt)
+{
+    HapContext *ctx = avctx->priv_data;
+    ThreadFrame tframe;
+    int ret, length;
+    int blocks = avctx->coded_width * avctx->coded_height / (TEXTURE_BLOCK_W * TEXTURE_BLOCK_H);
+
+    bytestream2_init(&ctx->gbc, avpkt->data, avpkt->size);
+
+    /* Check for section header */
+    length = parse_section_header(avctx);
+    if (length < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Frame is too small.\n");
+        return length;
+    }
+
+    /* Prepare the texture buffer and decompress function */
+    ret = setup_texture(avctx, length);
+    if (ret < 0)
+        return ret;
+
+    /* Get the output frame ready to receive data */
+    tframe.f = data;
+    ret = ff_thread_get_buffer(avctx, &tframe, 0);
+    if (ret < 0)
+        return ret;
+    ff_thread_finish_setup(avctx);
+
+    /* Use the decompress function on the texture, one block per thread */
+    avctx->execute2(avctx, decompress_texture_thread, tframe.f, NULL, blocks);
+
+    /* Frame is ready to be output */
+    tframe.f->pict_type = AV_PICTURE_TYPE_I;
+    tframe.f->key_frame = 1;
+    *got_frame = 1;
+
+    return avpkt->size;
+}
+
+static av_cold int hap_init(AVCodecContext *avctx)
+{
+    HapContext *ctx = avctx->priv_data;
+    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;
+    }
+
+    /* Since codec is based on 4x4 blocks, size is aligned to 4 */
+    avctx->coded_width  = FFALIGN(avctx->width,  TEXTURE_BLOCK_W);
+    avctx->coded_height = FFALIGN(avctx->height, TEXTURE_BLOCK_H);
+
+    /* Technically only one mode has alpha, but 32 bits are easier to handle */
+    avctx->pix_fmt = AV_PIX_FMT_RGBA;
+
+    ff_texturedsp_init(&ctx->dxtc);
+
+    return 0;
+}
+
+static av_cold int hap_close(AVCodecContext *avctx)
+{
+    HapContext *ctx = avctx->priv_data;
+
+    av_freep(&ctx->snappied);
+
+    return 0;
+}
+
+AVCodec ff_hap_decoder = {
+    .name           = "hap",
+    .long_name      = NULL_IF_CONFIG_SMALL("Vidvox Hap decoder"),
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_HAP,
+    .init           = hap_init,
+    .decode         = hap_decode,
+    .close          = hap_close,
+    .priv_data_size = sizeof(HapContext),
+    .capabilities   = CODEC_CAP_FRAME_THREADS | CODEC_CAP_SLICE_THREADS |
+                      CODEC_CAP_DR1,
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE |
+                      FF_CODEC_CAP_INIT_CLEANUP,
+};