From 07761294fc3f08e139e8a406ef7d5b63aaf1ecee Mon Sep 17 00:00:00 2001 From: Peter Ross Date: Mon, 17 Dec 2012 20:37:54 +1100 Subject: Silicon Graphics RLE 8-bit video decoder Signed-off-by: Vittorio Giovara --- libavcodec/sgirledec.c | 160 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 160 insertions(+) create mode 100644 libavcodec/sgirledec.c (limited to 'libavcodec/sgirledec.c') diff --git a/libavcodec/sgirledec.c b/libavcodec/sgirledec.c new file mode 100644 index 0000000000..d7bc5a9ea4 --- /dev/null +++ b/libavcodec/sgirledec.c @@ -0,0 +1,160 @@ +/* + * Silicon Graphics RLE 8-bit video decoder + * Copyright (c) 2012 Peter Ross + * + * 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 + * Silicon Graphics RLE 8-bit video decoder + * @note Data is packed in rbg323 with rle, contained in mv or mov. + * The algorithm and pixfmt are subtly different from SGI images. + */ + +#include "libavutil/common.h" + +#include "avcodec.h" +#include "internal.h" + +typedef struct SGIRLEContext { + AVFrame *frame; +} SGIRLEContext; + +static av_cold int sgirle_decode_init(AVCodecContext *avctx) +{ + SGIRLEContext *s = avctx->priv_data; + avctx->pix_fmt = AV_PIX_FMT_BGR8; + s->frame = av_frame_alloc(); + if (!s->frame) + return AVERROR(ENOMEM); + return 0; +} + +/** + * Convert SGI RBG323 pixel into AV_PIX_FMT_BGR8 + * SGI RGB data is packed as 8bpp, (msb)3R 2B 3G(lsb) + */ +#define RBG323_TO_BGR8(x) (((x << 3) & 0xC0) | \ + ((x << 3) & 0x38) | \ + ((x >> 5) & 7)) +static av_always_inline +void rbg323_to_bgr8(uint8_t *dst, const uint8_t *src, int size) +{ + int i; + for (i = 0; i < size; i++) + dst[i] = RBG323_TO_BGR8(src[i]); +} + +/** + * @param[out] dst Destination buffer + * @param[in] src Source buffer + * @param src_size Source buffer size (bytes) + * @param width Width of destination buffer (pixels) + * @param height Height of destination buffer (pixels) + * @param linesize Line size of destination buffer (bytes) + * + * @return <0 on error + */ +static int decode_sgirle8(AVCodecContext *avctx, uint8_t *dst, + const uint8_t *src, int src_size, + int width, int height, ptrdiff_t linesize) +{ + const uint8_t *src_end = src + src_size; + int x = 0, y = 0; + +#define INC_XY(n) \ + x += n; \ + if (x >= width) { \ + y++; \ + if (y >= height) \ + return 0; \ + x = 0; \ + } + + while (src_end - src >= 2) { + uint8_t v = *src++; + if (v > 0 && v < 0xC0) { + do { + int length = FFMIN(v, width - x); + if (length <= 0) + break; + memset(dst + y * linesize + x, RBG323_TO_BGR8(*src), length); + INC_XY(length); + v -= length; + } while (v > 0); + src++; + } else if (v >= 0xC1) { + v -= 0xC0; + do { + int length = FFMIN3(v, width - x, src_end - src); + if (src_end - src < length || length <= 0) + break; + rbg323_to_bgr8(dst + y * linesize + x, src, length); + INC_XY(length); + src += length; + v -= length; + } while (v > 0); + } else { + av_log(avctx, AV_LOG_ERROR, "Invalid opcode %d.\n", v); + return AVERROR_INVALIDDATA; + } + } + return 0; +} + +static int sgirle_decode_frame(AVCodecContext *avctx, void *data, + int *got_frame, AVPacket *avpkt) +{ + SGIRLEContext *s = avctx->priv_data; + int ret; + + if ((ret = ff_reget_buffer(avctx, s->frame)) < 0) + return ret; + + ret = decode_sgirle8(avctx, s->frame->data[0], avpkt->data, avpkt->size, + avctx->width, avctx->height, s->frame->linesize[0]); + if (ret < 0) + return ret; + + *got_frame = 1; + if ((ret = av_frame_ref(data, s->frame)) < 0) + return ret; + + return avpkt->size; +} + +static av_cold int sgirle_decode_end(AVCodecContext *avctx) +{ + SGIRLEContext *s = avctx->priv_data; + + av_frame_free(&s->frame); + + return 0; +} + +AVCodec ff_sgirle_decoder = { + .name = "sgirle", + .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics RLE 8-bit video"), + .type = AVMEDIA_TYPE_VIDEO, + .id = AV_CODEC_ID_SGIRLE, + .priv_data_size = sizeof(SGIRLEContext), + .init = sgirle_decode_init, + .close = sgirle_decode_end, + .decode = sgirle_decode_frame, + .capabilities = CODEC_CAP_DR1, +}; -- cgit v1.2.3