diff options
Diffstat (limited to 'libavcodec/sgirledec.c')
| -rw-r--r-- | libavcodec/sgirledec.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/libavcodec/sgirledec.c b/libavcodec/sgirledec.c new file mode 100644 index 0000000000..fd3cc5e78a --- /dev/null +++ b/libavcodec/sgirledec.c @@ -0,0 +1,151 @@ +/* + * SGI RLE 8-bit decoder + * Copyright (c) 2012 Peter Ross + * + * 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 + */ + +/** + * @file + * SGI RLE 8-bit decoder + */ + +#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 RGB332 pixel into AV_PIX_FMT_BGR8 + * SGI RGB332 is packed RGB 3:3:2, 8bpp, (msb)3R 2B 3G(lsb) + */ +#define RGB332_TO_BGR8(x) (((x << 3) & 0xC0) | ((x << 3) & 0x38) | ((x >> 5) & 7)) + +static av_always_inline void memcpy_rgb332_to_bgr8(uint8_t *dst, const uint8_t *src, int size) +{ + int i; + for (i = 0; i < size; i++) + dst[i] = RGB332_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, int 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, RGB332_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; + memcpy_rgb332_to_bgr8(dst + y*linesize + x, src, length); + INC_XY(length); + src += length; + v -= length; + } while (v > 0); + } else { + avpriv_request_sample(avctx, "opcode %d", v); + return AVERROR_PATCHWELCOME; + } + } + 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("SGI RLE 8-bit"), + .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, +}; |