1/*
2 * The default get_buffer2() implementation
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21#include <stdint.h>
22
23#include "libavutil/avassert.h"
24#include "libavutil/avutil.h"
25#include "libavutil/buffer.h"
26#include "libavutil/frame.h"
27#include "libavutil/hwcontext.h"
28#include "libavutil/imgutils.h"
29#include "libavutil/mem.h"
30#include "libavutil/samplefmt.h"
31#include "libavutil/version.h"
32
33#include "avcodec.h"
34#include "internal.h"
35
36typedef struct FramePool {
37    /**
38     * Pools for each data plane. For audio all the planes have the same size,
39     * so only pools[0] is used.
40     */
41    AVBufferPool *pools[4];
42
43    /*
44     * Pool parameters
45     */
46    int format;
47    int width, height;
48    int stride_align[AV_NUM_DATA_POINTERS];
49    int linesize[4];
50    int planes;
51    int channels;
52    int samples;
53} FramePool;
54
55static void frame_pool_free(void *opaque, uint8_t *data)
56{
57    FramePool *pool = (FramePool*)data;
58    int i;
59
60    for (i = 0; i < FF_ARRAY_ELEMS(pool->pools); i++)
61        av_buffer_pool_uninit(&pool->pools[i]);
62
63    av_freep(&data);
64}
65
66static AVBufferRef *frame_pool_alloc(void)
67{
68    FramePool *pool = av_mallocz(sizeof(*pool));
69    AVBufferRef *buf;
70
71    if (!pool)
72        return NULL;
73
74    buf = av_buffer_create((uint8_t*)pool, sizeof(*pool),
75                           frame_pool_free, NULL, 0);
76    if (!buf) {
77        av_freep(&pool);
78        return NULL;
79    }
80
81    return buf;
82}
83
84static int update_frame_pool(AVCodecContext *avctx, AVFrame *frame)
85{
86    FramePool *pool = avctx->internal->pool ?
87                      (FramePool*)avctx->internal->pool->data : NULL;
88    AVBufferRef *pool_buf;
89    int i, ret, ch, planes;
90
91    if (avctx->codec_type == AVMEDIA_TYPE_AUDIO) {
92        int planar = av_sample_fmt_is_planar(frame->format);
93        ch     = frame->ch_layout.nb_channels;
94#if FF_API_OLD_CHANNEL_LAYOUT
95FF_DISABLE_DEPRECATION_WARNINGS
96        if (!ch)
97            ch = frame->channels;
98FF_ENABLE_DEPRECATION_WARNINGS
99#endif
100        planes = planar ? ch : 1;
101    }
102
103    if (pool && pool->format == frame->format) {
104        if (avctx->codec_type == AVMEDIA_TYPE_VIDEO &&
105            pool->width == frame->width && pool->height == frame->height)
106            return 0;
107        if (avctx->codec_type == AVMEDIA_TYPE_AUDIO && pool->planes == planes &&
108            pool->channels == ch && frame->nb_samples == pool->samples)
109            return 0;
110    }
111
112    pool_buf = frame_pool_alloc();
113    if (!pool_buf)
114        return AVERROR(ENOMEM);
115    pool = (FramePool*)pool_buf->data;
116
117    switch (avctx->codec_type) {
118    case AVMEDIA_TYPE_VIDEO: {
119        int linesize[4];
120        int w = frame->width;
121        int h = frame->height;
122        int unaligned;
123        ptrdiff_t linesize1[4];
124        size_t size[4];
125
126        avcodec_align_dimensions2(avctx, &w, &h, pool->stride_align);
127
128        do {
129            // NOTE: do not align linesizes individually, this breaks e.g. assumptions
130            // that linesize[0] == 2*linesize[1] in the MPEG-encoder for 4:2:2
131            ret = av_image_fill_linesizes(linesize, avctx->pix_fmt, w);
132            if (ret < 0)
133                goto fail;
134            // increase alignment of w for next try (rhs gives the lowest bit set in w)
135            w += w & ~(w - 1);
136
137            unaligned = 0;
138            for (i = 0; i < 4; i++)
139                unaligned |= linesize[i] % pool->stride_align[i];
140        } while (unaligned);
141
142        for (i = 0; i < 4; i++)
143            linesize1[i] = linesize[i];
144        ret = av_image_fill_plane_sizes(size, avctx->pix_fmt, h, linesize1);
145        if (ret < 0)
146            goto fail;
147
148        for (i = 0; i < 4; i++) {
149            pool->linesize[i] = linesize[i];
150            if (size[i]) {
151                if (size[i] > INT_MAX - (16 + STRIDE_ALIGN - 1)) {
152                    ret = AVERROR(EINVAL);
153                    goto fail;
154                }
155                pool->pools[i] = av_buffer_pool_init(size[i] + 16 + STRIDE_ALIGN - 1,
156                                                     CONFIG_MEMORY_POISONING ?
157                                                        NULL :
158                                                        av_buffer_allocz);
159                if (!pool->pools[i]) {
160                    ret = AVERROR(ENOMEM);
161                    goto fail;
162                }
163            }
164        }
165        pool->format = frame->format;
166        pool->width  = frame->width;
167        pool->height = frame->height;
168
169        break;
170        }
171    case AVMEDIA_TYPE_AUDIO: {
172        ret = av_samples_get_buffer_size(&pool->linesize[0], ch,
173                                         frame->nb_samples, frame->format, 0);
174        if (ret < 0)
175            goto fail;
176
177        pool->pools[0] = av_buffer_pool_init(pool->linesize[0], NULL);
178        if (!pool->pools[0]) {
179            ret = AVERROR(ENOMEM);
180            goto fail;
181        }
182
183        pool->format     = frame->format;
184        pool->planes     = planes;
185        pool->channels   = ch;
186        pool->samples = frame->nb_samples;
187        break;
188        }
189    default: av_assert0(0);
190    }
191
192    av_buffer_unref(&avctx->internal->pool);
193    avctx->internal->pool = pool_buf;
194
195    return 0;
196fail:
197    av_buffer_unref(&pool_buf);
198    return ret;
199}
200
201static int audio_get_buffer(AVCodecContext *avctx, AVFrame *frame)
202{
203    FramePool *pool = (FramePool*)avctx->internal->pool->data;
204    int planes = pool->planes;
205    int i;
206
207    frame->linesize[0] = pool->linesize[0];
208
209    if (planes > AV_NUM_DATA_POINTERS) {
210        frame->extended_data = av_calloc(planes, sizeof(*frame->extended_data));
211        frame->nb_extended_buf = planes - AV_NUM_DATA_POINTERS;
212        frame->extended_buf  = av_calloc(frame->nb_extended_buf,
213                                          sizeof(*frame->extended_buf));
214        if (!frame->extended_data || !frame->extended_buf) {
215            av_freep(&frame->extended_data);
216            av_freep(&frame->extended_buf);
217            return AVERROR(ENOMEM);
218        }
219    } else {
220        frame->extended_data = frame->data;
221        av_assert0(frame->nb_extended_buf == 0);
222    }
223
224    for (i = 0; i < FFMIN(planes, AV_NUM_DATA_POINTERS); i++) {
225        frame->buf[i] = av_buffer_pool_get(pool->pools[0]);
226        if (!frame->buf[i])
227            goto fail;
228        frame->extended_data[i] = frame->data[i] = frame->buf[i]->data;
229    }
230    for (i = 0; i < frame->nb_extended_buf; i++) {
231        frame->extended_buf[i] = av_buffer_pool_get(pool->pools[0]);
232        if (!frame->extended_buf[i])
233            goto fail;
234        frame->extended_data[i + AV_NUM_DATA_POINTERS] = frame->extended_buf[i]->data;
235    }
236
237    if (avctx->debug & FF_DEBUG_BUFFERS)
238        av_log(avctx, AV_LOG_DEBUG, "default_get_buffer called on frame %p", frame);
239
240    return 0;
241fail:
242    av_frame_unref(frame);
243    return AVERROR(ENOMEM);
244}
245
246static int video_get_buffer(AVCodecContext *s, AVFrame *pic)
247{
248    FramePool *pool = (FramePool*)s->internal->pool->data;
249    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pic->format);
250    int i;
251
252    if (pic->data[0] || pic->data[1] || pic->data[2] || pic->data[3]) {
253        av_log(s, AV_LOG_ERROR, "pic->data[*]!=NULL in avcodec_default_get_buffer\n");
254        return -1;
255    }
256
257    if (!desc) {
258        av_log(s, AV_LOG_ERROR,
259            "Unable to get pixel format descriptor for format %s\n",
260            av_get_pix_fmt_name(pic->format));
261        return AVERROR(EINVAL);
262    }
263
264    memset(pic->data, 0, sizeof(pic->data));
265    pic->extended_data = pic->data;
266
267    for (i = 0; i < 4 && pool->pools[i]; i++) {
268        pic->linesize[i] = pool->linesize[i];
269
270        pic->buf[i] = av_buffer_pool_get(pool->pools[i]);
271        if (!pic->buf[i])
272            goto fail;
273
274        pic->data[i] = pic->buf[i]->data;
275    }
276    for (; i < AV_NUM_DATA_POINTERS; i++) {
277        pic->data[i] = NULL;
278        pic->linesize[i] = 0;
279    }
280
281    if (s->debug & FF_DEBUG_BUFFERS)
282        av_log(s, AV_LOG_DEBUG, "default_get_buffer called on pic %p\n", pic);
283
284    return 0;
285fail:
286    av_frame_unref(pic);
287    return AVERROR(ENOMEM);
288}
289
290int avcodec_default_get_buffer2(AVCodecContext *avctx, AVFrame *frame, int flags)
291{
292    int ret;
293
294    if (avctx->hw_frames_ctx) {
295        ret = av_hwframe_get_buffer(avctx->hw_frames_ctx, frame, 0);
296        frame->width  = avctx->coded_width;
297        frame->height = avctx->coded_height;
298        return ret;
299    }
300
301    if ((ret = update_frame_pool(avctx, frame)) < 0)
302        return ret;
303
304    switch (avctx->codec_type) {
305    case AVMEDIA_TYPE_VIDEO:
306        return video_get_buffer(avctx, frame);
307    case AVMEDIA_TYPE_AUDIO:
308        return audio_get_buffer(avctx, frame);
309    default:
310        return -1;
311    }
312}
313