brender_pix: a new image decoder

PIX is an image file format that was used by the BRender 3d engine.

Signed-off-by: Aleksi Nurmi <aleksi.nurmi@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 243 insertions, 0 deletions

diff --git a/libavcodec/brender_pix.c b/libavcodec/brender_pix.c
new file mode 100644
index 0000000000..84402553f0
--- /dev/null
+++ b/libavcodec/brender_pix.c
@@ -0,0 +1,243 @@
+/*
+ * BRender PIX (.pix) image decoder
+ * Copyright (c) 2012 Aleksi Nurmi
+ *
+ * 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
+ */
+
+/*
+ * Tested against samples from I-War / Independence War and Defiance.
+ * If the PIX file does not contain a palette, the
+ * palette_has_changed property of the AVFrame is set to 0.
+ */
+
+#include "libavutil/imgutils.h"
+#include "avcodec.h"
+#include "bytestream.h"
+
+typedef struct BRPixContext {
+    AVFrame frame;
+} BRPixContext;
+
+typedef struct BRPixHeader {
+    int format;
+    unsigned int width, height;
+} BRPixHeader;
+
+static av_cold int brpix_init(AVCodecContext *avctx)
+{
+    BRPixContext *s = avctx->priv_data;
+
+    avcodec_get_frame_defaults(&s->frame);
+    avctx->coded_frame = &s->frame;
+
+    return 0;
+}
+
+static int brpix_decode_header(BRPixHeader *out, GetByteContext *pgb)
+{
+    unsigned int header_len = bytestream2_get_be32(pgb);
+
+    out->format = bytestream2_get_byte(pgb);
+    bytestream2_skip(pgb, 2);
+    out->width = bytestream2_get_be16(pgb);
+    out->height = bytestream2_get_be16(pgb);
+
+    // the header is at least 11 bytes long; we read the first 7
+    if (header_len < 11) {
+        return 0;
+    }
+
+    // skip the rest of the header
+    bytestream2_skip(pgb, header_len-7);
+
+    return 1;
+}
+
+static int brpix_decode_frame(AVCodecContext *avctx,
+                              void *data, int *data_size_out,
+                              AVPacket *avpkt)
+{
+    BRPixContext *s = avctx->priv_data;
+    AVFrame *frame_out = data;
+
+    int ret;
+    GetByteContext gb;
+
+    unsigned int bytes_pp;
+
+    unsigned int magic[4];
+    unsigned int chunk_type;
+    unsigned int data_len;
+    BRPixHeader hdr;
+
+    bytestream2_init(&gb, avpkt->data, avpkt->size);
+
+    magic[0] = bytestream2_get_be32(&gb);
+    magic[1] = bytestream2_get_be32(&gb);
+    magic[2] = bytestream2_get_be32(&gb);
+    magic[3] = bytestream2_get_be32(&gb);
+
+    if (magic[0] != 0x12 ||
+        magic[1] != 0x8 ||
+        magic[2] != 0x2 ||
+        magic[3] != 0x2) {
+        av_log(avctx, AV_LOG_ERROR, "Not a BRender PIX file\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    chunk_type = bytestream2_get_be32(&gb);
+    if (chunk_type != 0x3 && chunk_type != 0x3d) {
+        av_log(avctx, AV_LOG_ERROR, "Invalid chunk type %d\n", chunk_type);
+        return AVERROR_INVALIDDATA;
+    }
+
+    ret = brpix_decode_header(&hdr, &gb);
+    if (!ret) {
+        av_log(avctx, AV_LOG_ERROR, "Invalid header length\n");
+        return AVERROR_INVALIDDATA;
+    }
+    switch (hdr.format) {
+    case 3:
+        avctx->pix_fmt = AV_PIX_FMT_PAL8;
+        bytes_pp = 1;
+        break;
+    case 4:
+        avctx->pix_fmt = AV_PIX_FMT_RGB555BE;
+        bytes_pp = 2;
+        break;
+    case 5:
+        avctx->pix_fmt = AV_PIX_FMT_RGB565BE;
+        bytes_pp = 2;
+        break;
+    case 6:
+        avctx->pix_fmt = AV_PIX_FMT_RGB24;
+        bytes_pp = 3;
+        break;
+    case 7:
+        avctx->pix_fmt = AV_PIX_FMT_0RGB;
+        bytes_pp = 4;
+        break;
+    case 18:
+        avctx->pix_fmt = AV_PIX_FMT_GRAY8A;
+        bytes_pp = 2;
+        break;
+    default:
+        av_log(avctx, AV_LOG_ERROR, "Format %d is not supported\n",
+                                    hdr.format);
+        return AVERROR_PATCHWELCOME;
+    }
+
+    if (s->frame.data[0])
+        avctx->release_buffer(avctx, &s->frame);
+
+    if (av_image_check_size(hdr.width, hdr.height, 0, avctx) < 0)
+        return AVERROR_INVALIDDATA;
+
+    if (hdr.width != avctx->width || hdr.height != avctx->height)
+        avcodec_set_dimensions(avctx, hdr.width, hdr.height);
+
+    if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return ret;
+    }
+
+    chunk_type = bytestream2_get_be32(&gb);
+
+    if (avctx->pix_fmt == AV_PIX_FMT_PAL8 &&
+        (chunk_type == 0x3 || chunk_type == 0x3d)) {
+        BRPixHeader palhdr;
+        uint32_t *pal_out = (uint32_t *)s->frame.data[1];
+
+        ret = brpix_decode_header(&palhdr, &gb);
+        if (!ret) {
+            av_log(avctx, AV_LOG_ERROR, "Invalid palette header length\n");
+            return AVERROR_INVALIDDATA;
+        }
+        if (palhdr.format != 7) {
+            av_log(avctx, AV_LOG_ERROR, "Palette is not in 0RGB format\n");
+            return AVERROR_INVALIDDATA;
+        }
+
+        chunk_type = bytestream2_get_be32(&gb);
+        data_len = bytestream2_get_be32(&gb);
+        bytestream2_skip(&gb, 8);
+        if (chunk_type != 0x21 || data_len != 1032 ||
+            bytestream2_get_bytes_left(&gb) < 1032) {
+            av_log(avctx, AV_LOG_ERROR, "Invalid palette data\n");
+            return AVERROR_INVALIDDATA;
+        }
+        // convert 0RGB to machine endian format (ARGB32)
+        for (int i = 0; i < 256; ++i) {
+            bytestream2_skipu(&gb, 1);
+            *pal_out++ = (0xFFU << 24) | bytestream2_get_be24u(&gb);
+        }
+        bytestream2_skip(&gb, 8);
+
+        s->frame.palette_has_changed = 1;
+
+        chunk_type = bytestream2_get_be32(&gb);
+    }
+
+    data_len = bytestream2_get_be32(&gb);
+    bytestream2_skip(&gb, 8);
+
+    // read the image data to the buffer
+    {
+        unsigned int bytes_per_scanline = bytes_pp * hdr.width;
+        unsigned int bytes_left = bytestream2_get_bytes_left(&gb);
+
+        if (chunk_type != 0x21 || data_len != bytes_left ||
+            bytes_left / bytes_per_scanline < hdr.height)
+        {
+            av_log(avctx, AV_LOG_ERROR, "Invalid image data\n");
+            return AVERROR_INVALIDDATA;
+        }
+
+        av_image_copy_plane(s->frame.data[0], s->frame.linesize[0],
+                            avpkt->data + bytestream2_tell(&gb),
+                            bytes_per_scanline,
+                            bytes_per_scanline, hdr.height);
+    }
+
+    *frame_out = s->frame;
+    *data_size_out = sizeof(AVFrame);
+
+    return avpkt->size;
+}
+
+static av_cold int brpix_end(AVCodecContext *avctx)
+{
+    BRPixContext *s = avctx->priv_data;
+
+    if(s->frame.data[0])
+        avctx->release_buffer(avctx, &s->frame);
+
+    return 0;
+}
+
+AVCodec ff_brender_pix_decoder = {
+    .name           = "brender_pix",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_BRENDER_PIX,
+    .priv_data_size = sizeof(BRPixContext),
+    .init           = brpix_init,
+    .close          = brpix_end,
+    .decode         = brpix_decode_frame,
+    .capabilities   = CODEC_CAP_DR1,
+    .long_name      = NULL_IF_CONFIG_SMALL("BRender PIX image"),
+};