/* * innoHeim/Rsupport Screen Capture Codec * Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com> * * 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 * innoHeim/Rsupport Screen Capture Codec decoder * * Fourcc: ISCC, RSCC * * Lossless codec, data stored in tiles, with optional deflate compression. * * Header contains the number of tiles in a frame with the tile coordinates, * and it can be deflated or not. Similarly, pixel data comes after the header * and a variable size value, and it can be deflated or just raw. * * Supports: PAL8, BGRA, BGR24, RGB555 */ #include <stdint.h> #include <string.h> #include <zlib.h> #include "libavutil/imgutils.h" #include "libavutil/internal.h" #include "avcodec.h" #include "bytestream.h" #include "codec_internal.h" #include "decode.h" #define TILE_SIZE 8 typedef struct Tile { int x, y; int w, h; } Tile; typedef struct RsccContext { GetByteContext gbc; AVFrame *reference; Tile *tiles; unsigned int tiles_size; int component_size; uint8_t palette[AVPALETTE_SIZE]; /* zlib interaction */ uint8_t *inflated_buf; uLongf inflated_size; int valid_pixels; } RsccContext; static av_cold int rscc_init(AVCodecContext *avctx) { RsccContext *ctx = avctx->priv_data; /* These needs to be set to estimate uncompressed buffer */ int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx); if (ret < 0) { av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n", avctx->width, avctx->height); return ret; } /* Allocate reference frame */ ctx->reference = av_frame_alloc(); if (!ctx->reference) return AVERROR(ENOMEM); /* Get pixel format and the size of the pixel */ if (avctx->codec_tag == MKTAG('I', 'S', 'C', 'C')) { if (avctx->extradata && avctx->extradata_size == 4) { if ((avctx->extradata[0] >> 1) & 1) { avctx->pix_fmt = AV_PIX_FMT_BGRA; ctx->component_size = 4; } else { avctx->pix_fmt = AV_PIX_FMT_BGR24; ctx->component_size = 3; } } else { avctx->pix_fmt = AV_PIX_FMT_BGRA; ctx->component_size = 4; } } else if (avctx->codec_tag == MKTAG('R', 'S', 'C', 'C')) { ctx->component_size = avctx->bits_per_coded_sample / 8; switch (avctx->bits_per_coded_sample) { case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break; case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555LE; break; case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break; case 32: avctx->pix_fmt = AV_PIX_FMT_BGR0; break; default: av_log(avctx, AV_LOG_ERROR, "Invalid bits per pixel value (%d)\n", avctx->bits_per_coded_sample); return AVERROR_INVALIDDATA; } } else { avctx->pix_fmt = AV_PIX_FMT_BGR0; ctx->component_size = 4; av_log(avctx, AV_LOG_WARNING, "Invalid codec tag\n"); } /* Store the value to check for keyframes */ ctx->inflated_size = avctx->width * avctx->height * ctx->component_size; /* Allocate maximum size possible, a full frame */ ctx->inflated_buf = av_malloc(ctx->inflated_size); if (!ctx->inflated_buf) return AVERROR(ENOMEM); return 0; } static av_cold int rscc_close(AVCodecContext *avctx) { RsccContext *ctx = avctx->priv_data; av_freep(&ctx->tiles); av_freep(&ctx->inflated_buf); av_frame_free(&ctx->reference); return 0; } static int rscc_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt) { RsccContext *ctx = avctx->priv_data; GetByteContext *gbc = &ctx->gbc; GetByteContext tiles_gbc; const uint8_t *pixels, *raw; uint8_t *inflated_tiles = NULL; int tiles_nb, packed_size, pixel_size = 0; int i, ret = 0; bytestream2_init(gbc, avpkt->data, avpkt->size); /* Size check */ if (bytestream2_get_bytes_left(gbc) < 12) { av_log(avctx, AV_LOG_ERROR, "Packet too small (%d)\n", avpkt->size); return AVERROR_INVALIDDATA; } /* Read number of tiles, and allocate the array */ tiles_nb = bytestream2_get_le16(gbc); if (tiles_nb == 0) { av_log(avctx, AV_LOG_DEBUG, "no tiles\n"); return avpkt->size; } av_fast_malloc(&ctx->tiles, &ctx->tiles_size, tiles_nb * sizeof(*ctx->tiles)); if (!ctx->tiles) { ret = AVERROR(ENOMEM); goto end; } av_log(avctx, AV_LOG_DEBUG, "Frame with %d tiles.\n", tiles_nb); /* When there are more than 5 tiles, they are packed together with * a size header. When that size does not match the number of tiles * times the tile size, it means it needs to be inflated as well */ if (tiles_nb > 5) { uLongf packed_tiles_size; if (tiles_nb < 32) packed_tiles_size = bytestream2_get_byte(gbc); else packed_tiles_size = bytestream2_get_le16(gbc); ff_dlog(avctx, "packed tiles of size %lu.\n", packed_tiles_size); /* If necessary, uncompress tiles, and hijack the bytestream reader */ if (packed_tiles_size != tiles_nb * TILE_SIZE) { uLongf length = tiles_nb * TILE_SIZE; if (bytestream2_get_bytes_left(gbc) < packed_tiles_size) { ret = AVERROR_INVALIDDATA; goto end; } inflated_tiles = av_malloc(length); if (!inflated_tiles) { ret = AVERROR(ENOMEM); goto end; } ret = uncompress(inflated_tiles, &length, gbc->buffer, packed_tiles_size); if (ret) { av_log(avctx, AV_LOG_ERROR, "Tile deflate error %d.\n", ret); ret = AVERROR_UNKNOWN; goto end; } /* Skip the compressed tile section in the main byte reader, * and point it to read the newly uncompressed data */ bytestream2_skip(gbc, packed_tiles_size); bytestream2_init(&tiles_gbc, inflated_tiles, length); gbc = &tiles_gbc; } } /* Fill in array of tiles, keeping track of how many pixels are updated */ for (i = 0; i < tiles_nb; i++) { ctx->tiles[i].x = bytestream2_get_le16(gbc); ctx->tiles[i].w = bytestream2_get_le16(gbc); ctx->tiles[i].y = bytestream2_get_le16(gbc); ctx->tiles[i].h = bytestream2_get_le16(gbc); if (pixel_size + ctx->tiles[i].w * (int64_t)ctx->tiles[i].h * ctx->component_size > INT_MAX) { av_log(avctx, AV_LOG_ERROR, "Invalid tile dimensions\n"); ret = AVERROR_INVALIDDATA; goto end; } pixel_size += ctx->tiles[i].w * ctx->tiles[i].h * ctx->component_size; ff_dlog(avctx, "tile %d orig(%d,%d) %dx%d.\n", i, ctx->tiles[i].x, ctx->tiles[i].y, ctx->tiles[i].w, ctx->tiles[i].h); if (ctx->tiles[i].w == 0 || ctx->tiles[i].h == 0) { av_log(avctx, AV_LOG_ERROR, "invalid tile %d at (%d.%d) with size %dx%d.\n", i, ctx->tiles[i].x, ctx->tiles[i].y, ctx->tiles[i].w, ctx->tiles[i].h); ret = AVERROR_INVALIDDATA; goto end; } else if (ctx->tiles[i].x + ctx->tiles[i].w > avctx->width || ctx->tiles[i].y + ctx->tiles[i].h > avctx->height) { av_log(avctx, AV_LOG_ERROR, "out of bounds tile %d at (%d.%d) with size %dx%d.\n", i, ctx->tiles[i].x, ctx->tiles[i].y, ctx->tiles[i].w, ctx->tiles[i].h); ret = AVERROR_INVALIDDATA; goto end; } } /* Reset the reader in case it had been modified before */ gbc = &ctx->gbc; /* Extract how much pixel data the tiles contain */ if (pixel_size < 0x100) packed_size = bytestream2_get_byte(gbc); else if (pixel_size < 0x10000) packed_size = bytestream2_get_le16(gbc); else if (pixel_size < 0x1000000) packed_size = bytestream2_get_le24(gbc); else packed_size = bytestream2_get_le32(gbc); ff_dlog(avctx, "pixel_size %d packed_size %d.\n", pixel_size, packed_size); if (packed_size < 0) { av_log(avctx, AV_LOG_ERROR, "Invalid tile size %d\n", packed_size); ret = AVERROR_INVALIDDATA; goto end; } /* Get pixels buffer, it may be deflated or just raw */ if (pixel_size == packed_size) { if (bytestream2_get_bytes_left(gbc) < pixel_size) { av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", pixel_size); ret = AVERROR_INVALIDDATA; goto end; } pixels = gbc->buffer; } else { uLongf len = ctx->inflated_size; if (bytestream2_get_bytes_left(gbc) < packed_size) { av_log(avctx, AV_LOG_ERROR, "Insufficient input for %d\n", packed_size); ret = AVERROR_INVALIDDATA; goto end; } if (ctx->inflated_size < pixel_size) { ret = AVERROR_INVALIDDATA; goto end; } ret = uncompress(ctx->inflated_buf, &len, gbc->buffer, packed_size); if (ret) { av_log(avctx, AV_LOG_ERROR, "Pixel deflate error %d.\n", ret); ret = AVERROR_UNKNOWN; goto end; } pixels = ctx->inflated_buf; } /* Allocate when needed */ ret = ff_reget_buffer(avctx, ctx->reference, 0); if (ret < 0) goto end; /* Pointer to actual pixels, will be updated when data is consumed */ raw = pixels; for (i = 0; i < tiles_nb; i++) { uint8_t *dst = ctx->reference->data[0] + ctx->reference->linesize[0] * (avctx->height - ctx->tiles[i].y - 1) + ctx->tiles[i].x * ctx->component_size; av_image_copy_plane(dst, -1 * ctx->reference->linesize[0], raw, ctx->tiles[i].w * ctx->component_size, ctx->tiles[i].w * ctx->component_size, ctx->tiles[i].h); raw += ctx->tiles[i].w * ctx->component_size * ctx->tiles[i].h; } /* Frame is ready to be output */ ret = av_frame_ref(frame, ctx->reference); if (ret < 0) goto end; /* Keyframe when the number of pixels updated matches the whole surface */ if (pixel_size == ctx->inflated_size) { frame->pict_type = AV_PICTURE_TYPE_I; frame->flags |= AV_FRAME_FLAG_KEY; } else { frame->pict_type = AV_PICTURE_TYPE_P; } /* Palette handling */ if (avctx->pix_fmt == AV_PIX_FMT_PAL8) { #if FF_API_PALETTE_HAS_CHANGED FF_DISABLE_DEPRECATION_WARNINGS frame->palette_has_changed = #endif ff_copy_palette(ctx->palette, avpkt, avctx); #if FF_API_PALETTE_HAS_CHANGED FF_ENABLE_DEPRECATION_WARNINGS #endif memcpy(frame->data[1], ctx->palette, AVPALETTE_SIZE); } // We only return a picture when enough of it is undamaged, this avoids copying nearly broken frames around if (ctx->valid_pixels < ctx->inflated_size) ctx->valid_pixels += pixel_size; if (ctx->valid_pixels >= ctx->inflated_size * (100 - avctx->discard_damaged_percentage) / 100) *got_frame = 1; ret = avpkt->size; end: av_free(inflated_tiles); return ret; } const FFCodec ff_rscc_decoder = { .p.name = "rscc", CODEC_LONG_NAME("innoHeim/Rsupport Screen Capture Codec"), .p.type = AVMEDIA_TYPE_VIDEO, .p.id = AV_CODEC_ID_RSCC, .init = rscc_init, FF_CODEC_DECODE_CB(rscc_decode_frame), .close = rscc_close, .priv_data_size = sizeof(RsccContext), .p.capabilities = AV_CODEC_CAP_DR1, .caps_internal = FF_CODEC_CAP_INIT_CLEANUP, };